tsnep: Add missing of_node_put() in tsnep_mdio_init()

The node pointer is returned by of_get_child_by_name() with
refcount incremented in tsnep_mdio_init(). Calling of_node_put()
to aovid the refcount leak in tsnep_mdio_init().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20211124084048.175456-1-yangyingliang@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/engleder/tsnep_main.c

@@ -1089,9 +1089,10 @@ static int tsnep_mdio_init(struct tsnep_adapter *adapter)
 	adapter->mdiobus->phy_mask = 0x0000001;
 
 	retval = of_mdiobus_register(adapter->mdiobus, np);
+
+out:
 	if (np)
 		of_node_put(np);
-out:
 
 	return retval;
 }