powerpc/corenet: Enable muxing MDIO buses via FPGA

Signed-off-by: Andy Fleming <afleming@gmail.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Shruti Kanetkar <Kanetkar.Shruti@gmail.com>
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

diff --cc arch/powerpc/configs/corenet32_smp_defconfig
Simple merge

diff --cc arch/powerpc/configs/corenet64_smp_defconfig
Simple merge

diff --cc arch/powerpc/platforms/85xx/corenet_generic.c
Simple merge