net: of_mdio: add of_mdiobus_link_phydev()

Add a function to walk the list of subnodes of a mdio bus and look for
a node that matches the phy's address with its 'reg' property. If found,
set the of_node pointer for the phy. This allows auto-probed pyh
devices to be augmented by information passed in via DT.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/phy/mdio_bus.c
Simple merge

diff --cc drivers/of/of_mdio.c
Simple merge

diff --cc include/linux/of_mdio.h
Simple merge