[netdrvr] fac_8xx build fix

drivers/net/fec_8xx/Kconfig

@@ -1,6 +1,6 @@
 config FEC_8XX
 	tristate "Motorola 8xx FEC driver"
-	depends on NET_ETHERNET
+	depends on NET_ETHERNET && FEC
 	select MII
 
 config FEC_8XX_GENERIC_PHY