dts: arm: Kinetis: Add base support for Kinetis

This patch adds DTS support and related files for the NXP Kinetis
platform.  The DTS files contain the base definitions for the hardware
nodes on Kinetis platforms.  The YAML files provide the definitions of
the contents of the DTS nodes.

The Kconfig changes were put in place to allow for the conversion of
existing drivers.  Once those drivers are modified, the Kconfig options
that are replaced by the DTS information will be removed.

Change-Id: If110fffa99c0b12471cf2df206da6687277e4756
Signed-off-by: Andy Gross <andy.gross@linaro.org>