Merge branch 'bridge-handle-changes-in-vlan_flag_bridge_binding'

Petr Machata says:

====================
bridge: Handle changes in VLAN_FLAG_BRIDGE_BINDING

When bridge binding is enabled on a VLAN netdevice, its link state should
track bridge ports that are members of the corresponding VLAN. This works
for a newly-added netdevices. However toggling the option does not have the
effect of enabling or disabling the behavior as appropriate.

In this patchset, have bridge react to bridge_binding toggles on VLAN
uppers.

There has been another attempt at supporting this behavior in 2022 by
Sevinj Aghayeva [0]. A discussion ensued that informed how this new
patchset is constructed, namely that the logic is in the bridge as opposed
to the 8021q driver, and the bridge reacts to NETDEV_CHANGE events on the
8021q upper.

Patches #1 and #2 contain the implementation, patches #3 and #4 a
selftest.

[0] https://lore.kernel.org/netdev/cover.1660100506.git.sevinj.aghayeva@gmail.com/
====================

Link: https://patch.msgid.link/cover.1734540770.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>