net: mdiobus: add clause 45 mdiobus accessors

There is a recurring pattern throughout some of the PHY code converting
a devad and regnum to our packed clause 45 representation. Rather than
having this scattered around the code, let's put a common translation
function in mdio.h, and provide some register accessors.

Convert the phylib core, phylink, bcm87xx and cortina to use these.

Signed-off-by: Russell King <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
8 files changed