This introduces two helper functions to create or destroy MDIO
interface. No logical changes introduced except the proper MDIO
names are given when having more than one MDIO bus.
Signed-off-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>