Merge branch 'fdb-entries-on-dsa-lag-interfaces'

Vladimir Oltean says:

====================
FDB entries on DSA LAG interfaces

This work permits having static and local FDB entries on LAG interfaces
that are offloaded by DSA ports. New API needs to be introduced in
drivers. To maintain consistency with the bridging offload code, I've
taken the liberty to reorganize the data structures added by Tobias in
the DSA core a little bit.

Tested on NXP LS1028A (felix switch). Would appreciate feedback/testing
on other platforms too. Testing procedure was the one described here:
https://patchwork.kernel.org/project/netdevbpf/cover/20210205130240.4072854-1-vladimir.oltean@nxp.com/

with this script:

ip link del bond0
ip link add bond0 type bond mode 802.3ad
ip link set swp1 down && ip link set swp1 master bond0 && ip link set swp1 up
ip link set swp2 down && ip link set swp2 master bond0 && ip link set swp2 up
ip link del br0
ip link add br0 type bridge && ip link set br0 up
ip link set br0 arp off
ip link set bond0 master br0 && ip link set bond0 up
ip link set swp0 master br0 && ip link set swp0 up
ip link set dev bond0 type bridge_slave flood off learning off
bridge fdb add dev bond0 <mac address of other eno0> master static

I'm noticing a problem in 'bridge fdb dump' with the 'self' entries, and
I didn't solve this. On Ocelot, an entry learned on a LAG is reported as
being on the first member port of it (so instead of saying 'self bond0',
it says 'self swp1'). This is better than not seeing the entry at all,
but when DSA queries for the FDBs on a port via ds->ops->port_fdb_dump,
it never queries for FDBs on a LAG. Not clear what we should do there,
we aren't in control of the ->ndo_fdb_dump of the bonding/team drivers.
Alternatively, we could just consider the 'self' entries reported via
ndo_fdb_dump as "better than nothing", and concentrate on the 'master'
entries that are in sync with the bridge when packets are flooded to
software.
====================

Link: https://lore.kernel.org/r/20220223140054.3379617-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>