Add DT binding doc for Broadcom MDIO bus multiplexer driver.
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NPramod Kumar <pramod.kumar@broadcom.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>