mlx4_en: remove sparse errors

Fix new sparse errors introduced in commit 6221217 (mlx4_en: dont
change mac_header on xmit)

Reported-by: Or Gerlitz <or.gerlitz@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/en_tx.c

@@ -686,8 +686,8 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	/* Copy dst mac address to wqe */
 	ethh = (struct ethhdr *)skb->data;
-	tx_desc->ctrl.srcrb_flags16[0] = get_unaligned((u16 *)ethh->h_dest);
-	tx_desc->ctrl.imm = get_unaligned((u32 *)(ethh->h_dest + 2));
+	tx_desc->ctrl.srcrb_flags16[0] = get_unaligned((__be16 *)ethh->h_dest);
+	tx_desc->ctrl.imm = get_unaligned((__be32 *)(ethh->h_dest + 2));
 	/* Handle LSO (TSO) packets */
 	if (lso_header_size) {
 		/* Mark opcode as LSO */