phylib: available for any speed ethernet

Several gigabit network drivers (SB1250_MAC, TIGON3, FSL, GIANFAR,
UCC_GETH, MV643XX_ETH, XILINX_LL_TEMAC, S6GMAC, STMMAC_ETH, PASEMI_MAC,
and OCTEON_ETHERNET) select PHYLIB.  These drivers are not under
NET_ETHERNET (10/100 mbit), so this warning is generated (long, irrelevant
parts are omitted):

warning: (NET_DSA && NET && EXPERIMENTAL && NET_ETHERNET && !S390 || ... || SB1250_MAC && NETDEVICES && NETDEV_1000 && SIBYTE_SB1xxx_SOC || TIGON3 && NETDEVICES && NETDEV_1000 && PCI || FSL_PQ_MDIO && NETDEVICES && NETDEV_1000 && FSL_SOC || GIANFAR && NETDEVICES && NETDEV_1000 && FSL_SOC || UCC_GETH && NETDEVICES && NETDEV_1000 && QUICC_ENGINE || MV643XX_ETH && NETDEVICES && NETDEV_1000 && (MV64X60 || PPC32 || PLAT_ORION) || XILINX_LL_TEMAC && NETDEVICES && NETDEV_1000 && (PPC || MICROBLAZE) || S6GMAC && NETDEVICES && NETDEV_1000 && XTENSA_VARIANT_S6000 || STMMAC_ETH && NETDEV_1000 && NETDEVICES && CPU_SUBTYPE_ST40 || PASEMI_MAC && NETDEVICES && NETDEV_10000 && PPC_PASEMI && PCI || OCTEON_ETHERNET && STAGING && !STAGING_EXCLUDE_BUILD && CPU_CAVIUM_OCTEON) selects PHYLIB which has unmet direct dependencies (!S390 && NET_ETHERNET)

PHYLIB is used by non-10/100 mbit ethernet drivers, so change the dependencies
to be NETDEVICES instead of NET_ETHERNET.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>