removed unnecessary locking, which might have created deadlocks. removed...

removed unnecessary locking, which might have created deadlocks. removed find_chan_by_l3id, since the l3id is not unique over all ports. removed automatic nt_stack reinitialization, since this creates segfaults.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@37323 65c4cc65-6c06-0410-ace0-fbb531ad65f3