ethernet :mellanox :mlx5: Replace pci_pool_alloc by pci_pool_zalloc

In alloc_cmd_box(), pci_pool_alloc() followed by memset will be
replaced by pci_pool_zalloc()
Signed-off-by: Souptick joarder <jrdr.linux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/cmd.c

@@ -1066,14 +1066,13 @@ static struct mlx5_cmd_mailbox *alloc_cmd_box(struct mlx5_core_dev *dev,
 	if (!mailbox)
 		return ERR_PTR(-ENOMEM);
 
-	mailbox->buf = pci_pool_alloc(dev->cmd.pool, flags,
-				      &mailbox->dma);
+	mailbox->buf = pci_pool_zalloc(dev->cmd.pool, flags,
+				       &mailbox->dma);
 	if (!mailbox->buf) {
 		mlx5_core_dbg(dev, "failed allocation\n");
 		kfree(mailbox);
 		return ERR_PTR(-ENOMEM);
 	}
-	memset(mailbox->buf, 0, sizeof(struct mlx5_cmd_prot_block));
 	mailbox->next = NULL;
 
 	return mailbox;