Channel selection in that mode must be forced, so that the TE nay not
select a different channel. In that mode the TE cannot know what
channel is allocated, so it cannot select a different channel.
Eumex PBX rejects calls without this fix.
* Use raw bchannel instead of DSP feature
* Removed DSP features
* Use new jitter buffer and control TX FIFO load by this application
* Added bridging daemon to assign time slots for bridging
When (exclusive or suggested) channel is offered, we must "seize" it, so that
it is linked with call instance. Still the channel might be changed on reply.