ethernet/fec: Add Vybrid family fec support

Freescale Vybrid platform implentments MAC-ENET core
providing compatibility with half- or full-duplex
10/100 Mbit/s Ethernet LANs.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>