Merge branch 'of_mdio'

Florian Fainelli says:

====================
net: of_mdio improvements

This patchset contains a few improvements to the MDIO device tree parsing
code such as refactoring and parsing the "max-speed" property which is
defined in the ePAPR specification.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>