Merge branch 'vlan-improvements-for-ocelot-switch'

Vladimir Oltean says:

====================
VLAN improvements for Ocelot switch

The main reason why I started this work is that deleting the bridge mdb
entries fails when the bridge is deleted, as described here:
https://lore.kernel.org/netdev/20201015173355.564934-1-vladimir.oltean@nxp.com/

In short, that happens because the bridge mdb entries are added with a
vid of 1, but deletion is attempted with a vid of 0. So the deletion
code fails to find the mdb entries.

The solution is to make ocelot use a pvid of 0 when it is under a bridge
with vlan_filtering 0. When vlan_filtering is 1, the pvid of the bridge
is what is programmed into the hardware.

The patch series also uncovers more bugs and does some more cleanup, but
the above is the main idea behind it.
====================

Link: https://lore.kernel.org/r/20201031102916.667619-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>