phylib: move to dynamic allocation of struct mii_bus

This patch introduces mdiobus_alloc() and mdiobus_free(), and
makes all mdio bus drivers use these functions to allocate their
struct mii_bus'es dynamically.

Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Andy Fleming <afleming@freescale.com>

drivers/net/sh_eth.c

@@ -1166,7 +1166,7 @@ out_free_irq:
 	kfree(mdp->mii_bus->irq);
 
 out_free_bus:
-	kfree(mdp->mii_bus);
+	free_mdio_bitbang(mdp->mii_bus);
 
 out_free_bitbang:
 	kfree(bitbang);