net: ethernet: mediatek: fix the missing of_node_put() after node is used done inside mtk_mdio_init

This patch adds the missing of_node_put() after finishing the usage
of of_get_child_by_name.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Acked-by: John Crispin <john@phrozen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mediatek/mtk_eth_soc.c

@@ -324,6 +324,7 @@ static int mtk_mdio_init(struct mtk_eth *eth)
 	err = of_mdiobus_register(eth->mii_bus, mii_np);
 	if (err)
 		goto err_free_bus;
+	of_node_put(mii_np);
 
 	return 0;