abnormal channel release WAS: Re: patches again

patch 40: in case of a channel breakdown, the signal handler for releasing lchan is called. the wrong pointer was used as lchan. (see last hunk) also we don't need to check use counter of lchan, if we receive an "cause 22 error". the lchan gets released anyway, if use counter becomes 0. (see first hunk). also i think we can force channel release when we receive an error indication. this can easily be tested: remove the battery during active call, then send a message to the mobile station (hang up on the remote). the message cannot be delivered, so the BTS send us an error indication, the channels and the call process gets released.