bsc: timeslot_fsm: Fix possible skip of some lchans in ts_terminate_lchan_fsms

If TS is in state changing from PDCH->TCH, the TCH lchan provoking the
switch would be skipped and not terminated before this patch.

See osmo-bsc I9cedb77d6578597f1febab36c54b2ee427c7a4a2 for similar
extensive explanation.

Change-Id: I9dc2a6e5b15376d049bd2ac5ddfa24340771b5c8
1 file changed