Use peerhangup flag variable to track whether a hangup has been
initiated by the peer or libpri itself (e.g. Layer 2 timeouts).
These changes fix a couple of problems with hangup events not being
handled properly in some situations:
- Call abort caused by incoming RESTART on a channel in use
- T309 timeout after L2 loss
- Improved hangup handling in libpri-side on_hangup() event handler
and state_advance() (FreeTDM side)
Signed-off-by: Stefan Knoblich <stkn@openisdn.net>
8c58a10999