net: mdiobus: release reset_gpio in mdiobus_unregister_device()

reset_gpio is claimed in mdiobus_register_device(), but it is not
released in mdiobus_unregister_device(). It is instead only
released when the whole MDIO bus is unregistered.
When a device uses the reset_gpio property, it becomes impossible
to unregister it and register it again, because the GPIO remains
claimed.
This patch resolves that issue.

Fixes: bafbdd5 ("phylib: Add device reset GPIO support") # see notes
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Cc: Csókás Bence <csokas.bence@prolan.hu>
[ csokas.bence: Resolve rebase conflict and clarify msg ]
Signed-off-by: Buday Csaba <buday.csaba@prolan.hu>
Link: https://patch.msgid.link/20250807135449.254254-2-csokas.bence@prolan.hu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Buday Csaba

drivers/net/phy/mdio_bus.c

@@ -91,6 +91,7 @@ int mdiobus_unregister_device(struct mdio_device *mdiodev)
 	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
 		return -EINVAL;
 
+	gpiod_put(mdiodev->reset_gpio);
 	reset_control_put(mdiodev->reset_ctrl);
 
 	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;

drivers/net/phy/mdio_bus_provider.c

@@ -443,9 +443,6 @@ void mdiobus_unregister(struct mii_bus *bus)
 		if (!mdiodev)
 			continue;
 
-		if (mdiodev->reset_gpio)
-			gpiod_put(mdiodev->reset_gpio);
-
 		mdiodev->device_remove(mdiodev);
 		mdiodev->device_free(mdiodev);
 	}