of_mdio: fix node leak in of_phy_register_fixed_link error path

BugLink: https://bugs.launchpad.net/bugs/1878232

commit 48c1699d upstream.

Make sure to drop the of_node reference also on failure to parse the
speed property in of_phy_register_fixed_link().

Fixes: 3be2a49e ("of: provide a binding for fixed link PHYs")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/of/of_mdio.c

@@ -334,8 +334,11 @@ int of_phy_register_fixed_link(struct device_node *np)
 		status.link = 1;
 		status.duplex = of_property_read_bool(fixed_link_node,
 						      "full-duplex");
-		if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
+		if (of_property_read_u32(fixed_link_node, "speed",
+					 &status.speed)) {
+			of_node_put(fixed_link_node);
 			return -EINVAL;
+		}
 		status.pause = of_property_read_bool(fixed_link_node, "pause");
 		status.asym_pause = of_property_read_bool(fixed_link_node,
 							  "asym-pause");