net: ethernet: Fix memleak in ethoc_probe

When mdiobus_register() fails, priv->mdio allocated
by mdiobus_alloc() has not been freed, which leads
to memleak.

Fixes: e7f4dc35 ("mdio: Move allocation of interrupts into core")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20201223110615.31389-1-dinghao.liu@zju.edu.cnSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/ethoc.c

@@ -1211,7 +1211,7 @@ static int ethoc_probe(struct platform_device *pdev)
 	ret = mdiobus_register(priv->mdio);
 	if (ret) {
 		dev_err(&netdev->dev, "failed to register MDIO bus\n");
-		goto free2;
+		goto free3;
 	}
 
 	ret = ethoc_mdio_probe(netdev);
@@ -1243,6 +1243,7 @@ static int ethoc_probe(struct platform_device *pdev)
 	netif_napi_del(&priv->napi);
 error:
 	mdiobus_unregister(priv->mdio);
+free3:
 	mdiobus_free(priv->mdio);
 free2:
 	clk_disable_unprepare(priv->clk);