net: usb: remove redundant null pointer check before of_node_put

of_node_put has taken the null pointer check into account. So it is
safe to remove the duplicated check before of_node_put.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/usb/lan78xx.c

@@ -1835,7 +1835,6 @@ static int lan78xx_mdio_init(struct lan78xx_net *dev)
 
 	node = of_get_child_by_name(dev->udev->dev.of_node, "mdio");
 	ret = of_mdiobus_register(dev->mdiobus, node);
-	if (node)
 	of_node_put(node);
 	if (ret) {
 		netdev_err(dev->net, "can't register MDIO bus\n");