dm: eth: Do not print misleading "Net Initialization Skipped"

With driver model, board_eth_init() or cpu_eth_init() is not a must.
Thus we don't need print a misleading "Net Initialization Skipped".

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/net/eth.c b/net/eth.c
index d3ec8d6..c46a8c3 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -107,7 +107,9 @@
 		if (cpu_eth_init(gd->bd) < 0)
 			printf("CPU Net Initialization Failed\n");
 	} else {
+#ifndef CONFIG_DM_ETH
 		printf("Net Initialization Skipped\n");
+#endif
 	}
 }