net: mdio: thunder: Fix a double free issue in the .remove function

'bus->mii_bus' have been allocated with 'devm_mdiobus_alloc_size()' in the
probe function. So it must not be freed explicitly or there will be a
double free.

Remove the incorrect 'mdiobus_free' in the remove function.

Fixes: 379d7ac7 ("phy: mdio-thunder: Add driver for Cavium Thunder SoC MDIO buses.")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/mdio/mdio-thunder.c

@@ -126,7 +126,6 @@ static void thunder_mdiobus_pci_remove(struct pci_dev *pdev)
 			continue;
 
 		mdiobus_unregister(bus->mii_bus);
-		mdiobus_free(bus->mii_bus);
 		oct_mdio_writeq(0, bus->register_base + SMI_EN);
 	}
 	pci_release_regions(pdev);