PPC: Drop mv6446x_eth_initialize() from net/eth.c

This function was defined as an extern in net/eth.c, drop that and use
standard means of calling it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefan Roese <sr@denx.de>

board/prodrive/p3mx/eth.h

@@ -39,5 +39,6 @@ int db64360_eth0_transmit(unsigned int s, volatile char *p);
 void db64360_eth0_disable(void);
 bool network_start(bd_t *bis);
 
+int mv6446x_eth_initialize(bd_t *);
 
 #endif /* __EVB64360_ETH_H__ */

board/prodrive/p3mx/p3mx.c

@@ -851,3 +851,8 @@ void my_remap_gt_regs_bootm (u32 cur_loc, u32 new_loc)
 	       != temp);
 
 }
+
+int board_eth_init(bd_t *bis)
+{
+	return mv6446x_eth_initialize(bis);
+}