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>
diff --git a/drivers/net/phy/mdio-bitbang.c b/drivers/net/phy/mdio-bitbang.c
index c01b780..2576055 100644
--- a/drivers/net/phy/mdio-bitbang.c
+++ b/drivers/net/phy/mdio-bitbang.c
@@ -165,7 +165,7 @@
 {
 	struct mii_bus *bus;
 
-	bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
+	bus = mdiobus_alloc();
 	if (!bus)
 		return NULL;
 
@@ -184,7 +184,7 @@
 	struct mdiobb_ctrl *ctrl = bus->priv;
 
 	module_put(ctrl->ops->owner);
-	kfree(bus);
+	mdiobus_free(bus);
 }
 EXPORT_SYMBOL(free_mdio_bitbang);