Add PCI Phy support for Broadcom Northstar2 SoCs.  This driver uses the
interface from the iproc mdio mux driver to enable the devices
respective phys.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NJon Mason <jonmason@broadcom.com>
Signed-off-by: NPramod Kumar <pramod.kumar@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>