Met a problem that mii command fails to work after u-boot booting up.
The root cause is the fec_probe function initializes ethernet PHY first,
then reset the FEC controller. This causes the mii_speed register reset
to 0 and lead mdio can't work.
Change the flow to reset FEC controller prior than setup PHY.

Signed-off-by: Ye Li <ye.li@nxp.com>