Merge net branch into master

Main changes:

- Documentation enhancements and fixes
- HTTP client sample application
- TCP fixes
- net_buf access fixes in IP stack
- IEEE 802.15.4 fragmentation fixes

----------------------------------------------------------------
Anas Nashif (1):
      net: nbuf: Fix style of doxygen comment

Flavio Santes (1):
      samples/net/http: Add the HTTP client sample application

Johann Fischer (1):
      drivers: mcr20a: control access to SPI with semaphore

Juan Manuel Cruz (2):
      drivers: enc28j60: Enables reception of multicast packets
      mbedtls: add arduino 101 configuration to ssl client sample

Jukka Rissanen (10):
      samples: net: Fix invalid memory access for TCP
      drivers/eth/mcux: Free net_buf using net_nbuf_unref
      net: ipv6: Fix pending buf leak when NA is received
      net: ipv6: Free received NA net_buf
      net: todo: Add CAN support entry
      net: nbuf: Add timeout to net_buf getters
      net: nbuf: Add helper to print fragment chain
      net: nbuf: Remove dead code in net_nbuf_compact()
      net: nbuf: Fix double free in net_nbuf_compact()
      net: arp: Fix the ethernet header location

Michael Scott (6):
      net: context: keep randomly assigned port for TCP bind() calls
      net: ip: change some error messages to NET_ERR
      net: context: fix net context / net conn leak
      samples: net: irc_bot: fix build break
      samples: net: irc_bot: fix size_t related build warnings
      samples: net: irc_bot: add testcase.ini

Ravi kumar Veeramally (4):
      net: fragment: Fix the 802.15.4 fragmentation
      net: tests: 15.4: Increase max data size and fix config option
      net: nbuf: Remove unused net_nbuf_push() API
      net: nbuf: Fix net_nbuf_compact() API

Tomasz Bursztyka (1):
      doc/net: Add L2 and device driver document

Wojciech Bober (2):
      drivers/ieee802154: Split drivers Kconfig
      drivers/net/ieee802154: Change configuration prefix

 boards/arm/frdm_k64f/pinmux.c                      |   2 +-
 .../x86/quark_se_c1000_devboard/Kconfig.defconfig  |  18 +-
 boards/x86/quark_se_c1000_devboard/board.c         |  14 +-
 boards/x86/quark_se_c1000_devboard/board.h         |  10 +-
 .../networking/connectivity-example-app.c          |   4 +-
 doc/subsystems/networking/l2-and-drivers.rst       | 154 +++++++++++
 doc/subsystems/networking/networking.rst           |   2 +-
 drivers/console/telnet_console.c                   |   6 +-
 drivers/ethernet/eth_enc28j60.c                    |   4 +-
 drivers/ethernet/eth_enc28j60_priv.h               |   3 +-
 drivers/ethernet/eth_mcux.c                        |  10 +-
 drivers/ethernet/eth_sam_gmac.c                    |   6 +-
 drivers/ieee802154/Kconfig                         | 190 +-------------
 drivers/ieee802154/Kconfig.cc2520                  |  67 +++++
 drivers/ieee802154/Kconfig.mcr20a                  | 120 +++++++++
 drivers/ieee802154/Makefile                        |  10 +-
 drivers/ieee802154/ieee802154_cc2520.c             |  37 +--
 drivers/ieee802154/ieee802154_cc2520.h             |   2 +-
 drivers/ieee802154/ieee802154_mcr20a.c             |  88 +++++--
 drivers/ieee802154/ieee802154_mcr20a.h             |   3 +-
 drivers/ieee802154/ieee802154_uart_pipe.c          |   6 +-
 drivers/slip/slip.c                                |   6 +-
 ext/hal/nxp/mcux/Makefile                          |   2 +-
 include/net/nbuf.h                                 | 200 +++++++++------
 samples/bluetooth/ipsp/src/main.c                  |   2 +-
 samples/net/coaps_client/src/udp.c                 |   4 +-
 samples/net/coaps_server/src/udp.c                 |   4 +-
 .../net/echo_client/prj_arduino_101_cc2520.conf    |  10 +-
 samples/net/echo_client/prj_cc2520.conf            |   4 +-
 samples/net/echo_client/prj_frdm_k64f_cc2520.conf  |  10 +-
 samples/net/echo_client/prj_frdm_k64f_mcr20a.conf  |   2 +-
 samples/net/echo_client/prj_qemu_802154.conf       |   2 +-
 samples/net/echo_client/src/Makefile               |   2 +-
 samples/net/echo_client/src/echo-client.c          |   5 +-
 .../net/echo_server/prj_arduino_101_cc2520.conf    |  10 +-
 samples/net/echo_server/prj_cc2520.conf            |   4 +-
 samples/net/echo_server/prj_frdm_k64f_cc2520.conf  |  10 +-
 samples/net/echo_server/prj_frdm_k64f_mcr20a.conf  |   2 +-
 samples/net/echo_server/prj_qemu_802154.conf       |   2 +-
 samples/net/echo_server/src/Makefile               |   2 +-
 samples/net/echo_server/src/echo-server.c          |   8 +-
 samples/net/http_client/Makefile                   |  10 +
 samples/net/http_client/README.rst                 | 229 +++++++++++++++++
 samples/net/http_client/prj_frdm_k64f.conf         |  34 +++
 samples/net/http_client/src/Makefile               |  11 +
 samples/net/http_client/src/config.h               |  74 ++++++
 samples/net/http_client/src/http_client.c          | 158 ++++++++++++
 samples/net/http_client/src/http_client.h          |  38 +++
 samples/net/http_client/src/http_client_cb.c       | 133 ++++++++++
 samples/net/http_client/src/http_client_cb.h       |  38 +++
 samples/net/http_client/src/http_client_rcv.c      | 101 ++++++++
 samples/net/http_client/src/http_client_rcv.h      |  15 ++
 samples/net/http_client/src/http_client_types.h    |  28 ++
 samples/net/http_client/src/main.c                 | 128 +++++++++
 samples/net/http_client/src/tcp_client.c           | 162 ++++++++++++
 samples/net/http_client/src/tcp_client.h           |  31 +++
 samples/net/http_client/testcase.ini               |   4 +
 samples/net/http_server/src/http_write_utils.c     |  10 +-
 samples/net/ieee802154/hw/prj.conf                 |   4 +-
 samples/net/ieee802154/hw/prj_mcr20a.conf          |   2 +-
 samples/net/ieee802154/hw/src/ieee802154_test.c    |   8 +-
 samples/net/ieee802154/qemu/prj.conf               |   2 +-
 .../net/ieee802154/qemu/src/ieee802154_qemu_test.c |   2 +-
 samples/net/irc_bot/src/irc-bot.c                  |   6 +-
 samples/net/irc_bot/testcase.ini                   |   4 +
 samples/net/leds_demo/prj_802154.conf              |   2 +-
 samples/net/leds_demo/src/leds-demo.c              |  16 +-
 samples/net/mbedtls_dtlsclient/src/udp.c           |   4 +-
 samples/net/mbedtls_dtlsserver/src/udp.c           |   4 +-
 samples/net/mbedtls_sslclient/Makefile             |   4 +-
 samples/net/mbedtls_sslclient/prj_arduino_101.conf |  34 +++
 samples/net/mbedtls_sslclient/src/tcp.c            |   4 +-
 samples/net/wpan_serial/prj.conf                   |   2 +-
 samples/net/wpan_serial/src/Makefile               |   2 +-
 samples/net/wpan_serial/src/main.c                 |  10 +-
 samples/net/wpanusb/prj.conf                       |   4 +-
 samples/net/wpanusb/src/Makefile                   |   8 +-
 samples/net/wpanusb/src/wpanusb.c                  |  15 +-
 samples/net/zoap_client/src/zoap-client.c          |   4 +-
 samples/net/zoap_server/prj_cc2520.conf            |   2 +-
 samples/net/zoap_server/src/zoap-server.c          |  40 +--
 samples/net/zperf/prj_quark_se_c1000_devboard.conf |   2 +-
 samples/net/zperf/src/zperf_tcp_uploader.c         |  11 +-
 samples/net/zperf/src/zperf_udp_receiver.c         |   4 +-
 samples/net/zperf/src/zperf_udp_uploader.c         |  18 +-
 subsys/net/TODO                                    |  16 ++
 subsys/net/ip/6lo.c                                |  21 +-
 subsys/net/ip/connection.c                         |   6 +-
 subsys/net/ip/dhcpv4.c                             |  38 ++-
 subsys/net/ip/icmpv4.c                             |   8 +-
 subsys/net/ip/icmpv6.c                             |  10 +-
 subsys/net/ip/ipv4.c                               |   2 +-
 subsys/net/ip/ipv6.c                               |  24 +-
 subsys/net/ip/l2/arp.c                             |  19 +-
 subsys/net/ip/l2/bluetooth.c                       |   4 +-
 subsys/net/ip/l2/ieee802154/ieee802154.c           |   4 +-
 subsys/net/ip/l2/ieee802154/ieee802154_fragment.c  | 137 ++++++----
 subsys/net/ip/l2/ieee802154/ieee802154_frame.c     |   4 +-
 subsys/net/ip/nbuf.c                               | 199 +++++++-------
 subsys/net/ip/net_context.c                        |  38 ++-
 subsys/net/ip/net_private.h                        |  29 +++
 subsys/net/ip/rpl.c                                |  21 +-
 subsys/net/ip/tcp.c                                |   6 +-
 subsys/net/lib/dns/dns_client.c                    |   4 +-
 subsys/net/lib/mqtt/mqtt.c                         |  20 +-
 subsys/net/lib/zoap/zoap_link_format.c             |   4 +-
 tests/net/6lo/src/main.c                           |   6 +-
 tests/net/arp/src/main.c                           |  24 +-
 tests/net/context/src/main.c                       |  24 +-
 tests/net/dhcpv4/src/main.c                        |   7 +-
 tests/net/ieee802154/fragment/prj.conf             |   2 +-
 tests/net/ieee802154/fragment/src/main.c           |  14 +-
 tests/net/ieee802154/l2/src/ieee802154_test.c      |   6 +-
 tests/net/iface/src/main.c                         |   4 +-
 tests/net/ipv6/src/main.c                          |  20 +-
 tests/net/nbuf/src/main.c                          | 285 +++++----------------
 tests/net/route/src/main.c                         |   4 +-
 tests/net/rpl/src/main.c                           |   4 +-
 tests/net/tcp/src/main.c                           |   8 +-
 tests/net/udp/src/main.c                           |   8 +-
 tests/net/utils/src/main.c                         |  34 +--
 121 files changed, 2503 insertions(+), 1030 deletions(-)
 create mode 100644 doc/subsystems/networking/l2-and-drivers.rst
 create mode 100644 drivers/ieee802154/Kconfig.cc2520
 create mode 100644 drivers/ieee802154/Kconfig.mcr20a
 create mode 100644 samples/net/http_client/Makefile
 create mode 100644 samples/net/http_client/README.rst
 create mode 100644 samples/net/http_client/prj_frdm_k64f.conf
 create mode 100644 samples/net/http_client/src/Makefile
 create mode 100644 samples/net/http_client/src/config.h
 create mode 100644 samples/net/http_client/src/http_client.c
 create mode 100644 samples/net/http_client/src/http_client.h
 create mode 100644 samples/net/http_client/src/http_client_cb.c
 create mode 100644 samples/net/http_client/src/http_client_cb.h
 create mode 100644 samples/net/http_client/src/http_client_rcv.c
 create mode 100644 samples/net/http_client/src/http_client_rcv.h
 create mode 100644 samples/net/http_client/src/http_client_types.h
 create mode 100644 samples/net/http_client/src/main.c
 create mode 100644 samples/net/http_client/src/tcp_client.c
 create mode 100644 samples/net/http_client/src/tcp_client.h
 create mode 100644 samples/net/http_client/testcase.ini
 create mode 100644 samples/net/irc_bot/testcase.ini
 create mode 100644 samples/net/mbedtls_sslclient/prj_arduino_101.conf

Change-Id: I2d92e41991f322c6d440f0545feee8f4d9a60edc
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>