batman-adv: tt: don't merge change entries with different VIDs

batman-adv: tt: don't merge change entries with different VIDs

batadv_tt_local_event() merges/cancels events for the same client which
would conflict or be duplicates. The matching of the queued events only
compares the MAC address - the VLAN ID stored in each event is ignored.

If a MAC would now appear on multiple VID, the two ADD change events (for
VID 1 and VID 2) would be merged to a single vid event. The remote can
therefore not calculate the correct TT table and desync. A full translation
table exchange is required to recover from this state.

A check of VID is therefore necessary to avoid such wrong merges/cancels.

Cc: stable@kernel.org
Fixes: c018ad3de61a ("batman-adv: add the VLAN ID attribute to the TT entry")
Signed-off-by: Sven Eckelmann <sven@narfation.org>