gianfar: Use kmemdup rather than duplicating its implementation

The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/freescale/gianfar_ethtool.c b/drivers/net/ethernet/freescale/gianfar_ethtool.c
index 1ea0eb9..5890f4b 100644
--- a/drivers/net/ethernet/freescale/gianfar_ethtool.c
+++ b/drivers/net/ethernet/freescale/gianfar_ethtool.c
@@ -1410,10 +1410,9 @@
 
 	/* We need a copy of the filer table because
 	 * we want to change its order */
-	temp_table = kmalloc(sizeof(*temp_table), GFP_KERNEL);
+	temp_table = kmemdup(tab, sizeof(*temp_table), GFP_KERNEL);
 	if (temp_table == NULL)
 		return -ENOMEM;
-	memcpy(temp_table, tab, sizeof(*temp_table));
 
 	mask_table = kcalloc(MAX_FILER_CACHE_IDX / 2 + 1,
 			sizeof(struct gfar_mask_entry), GFP_KERNEL);