Merge branch 'net-dsa-mv88e6xxx-port-mtu-support'

Merge branch 'net-dsa-mv88e6xxx-port-mtu-support'

Chris Packham says:

====================
net: dsa: mv88e6xxx: port mtu support

This series connects up the mv88e6xxx switches to the dsa infrastructure for
configuring the port MTU. The first patch is also a bug fix which might be a
candiatate for stable.

I've rebased this series on top of net-next/master to pick up Andrew's change
for the gigabit switches. Patch 1 and 2 are unchanged (aside from adding
Andrew's Reviewed-by). Patch 3 is reworked to make use of the existing mtu
support.
====================

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