infiniband: Replace memset with eth_zero_addr

Use eth_zero_addr to assign the zero address to the given address
array instead of memset when second argument is address of zero.

Signed-off-by: Lucas Tanure <tanure@linux.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx4/ah.c b/drivers/infiniband/hw/mlx4/ah.c
index 4fdb241..105246f 100644
--- a/drivers/infiniband/hw/mlx4/ah.c
+++ b/drivers/infiniband/hw/mlx4/ah.c
@@ -92,7 +92,7 @@
 				ah_attr->grh.sgid_index, &sgid, &gid_attr);
 	if (ret)
 		return ERR_PTR(ret);
-	memset(ah->av.eth.s_mac, 0, ETH_ALEN);
+	eth_zero_addr(ah->av.eth.s_mac);
 	if (gid_attr.ndev) {
 		if (is_vlan_dev(gid_attr.ndev))
 			vlan_tag = vlan_dev_vlan_id(gid_attr.ndev);