Moved initialization of MPC512x_FEC Ethernet driver to CPU directory

Added a cpu_eth_init() function to MPC512x CPU directory and
removed code from net/eth.c

Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/include/netdev.h b/include/netdev.h
index f28039e..487d319 100644
--- a/include/netdev.h
+++ b/include/netdev.h
@@ -49,6 +49,7 @@
 int macb_eth_initialize(int id, void *regs, unsigned int phy_addr);
 int mcdmafec_initialize(bd_t *bis);
 int mcffec_initialize(bd_t *bis);
+int mpc512x_fec_initialize(bd_t *bis);
 int natsemi_initialize(bd_t *bis);
 int ns8382x_initialize(bd_t *bis);
 int pcnet_initialize(bd_t *bis);