power: reset: linkstation-poweroff: add missing put_device()

The of_mdio_find_bus() takes a reference to the underlying device
structure, we should release that reference using a put_device() call.
Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

drivers/power/reset/linkstation-poweroff.c

@@ -113,6 +113,7 @@ static int __init linkstation_poweroff_init(void)
 		return -EPROBE_DEFER;
 
 	phydev = phy_find_first(bus);
+	put_device(&bus->dev);
 	if (!phydev)
 		return -EPROBE_DEFER;