net: dsa: Add missing of_node_put() in dsa_port_link_register_of

The device_node pointer is returned by of_parse_phandle()  with refcount
incremented. We should use of_node_put() on it when done.
of_node_put() will check for NULL value.

Fixes: a20f9970 ("net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dsa/port.c

@@ -1620,8 +1620,10 @@ int dsa_port_link_register_of(struct dsa_port *dp)
 			if (ds->ops->phylink_mac_link_down)
 				ds->ops->phylink_mac_link_down(ds, port,
 					MLO_AN_FIXED, PHY_INTERFACE_MODE_NA);
+			of_node_put(phy_np);
 			return dsa_port_phylink_register(dp);
 		}
+		of_node_put(phy_np);
 		return 0;
 	}