bridge: fix vlan(4) on a bridge member

[ivy]

Summary

If an interface is a bridge member, and a vlan(4) is also created on
that interface, and net.link.bridge.member_ifaddrs=0, then vlan(4)
will never see any incoming frames because bridge doesn't pass them
to the host for processing.

Work around this by checking for locally-addressed frames using the
MAC address of the interface we received the frame on, but only if
the frame has a .1q tag and there's a vlan trunk on the interface.

This behaviour is almost certainly "wrong" and it's not clear if we
really want to support this, but it did work in the past and the
member_ifaddrs change was not supposed to break it, so this restores
the previous behaviour.

PR: 287150
Tested by: Marek Zarychta <[e-mail]>
MFC after: 1 week

[ivy]

a better fix for this would be to check in bridge_input if the frame has a tag and there's a vlan trunk, and if so immediately return it to ether_input. however this change is intended to preserve the existing behaviour (prior to member_ifaddrs) so it can be MFC'd to stable/14 with less risk of breaking something else.