fsm: use deferred deallocation

Since osmo-bsc uses the MGCP client FSMs, it is required to enable this new
feature to guarantee safe operation. The issue is described in detail in commit
logs linked below.

Notably, osmo-msc currently chooses to omit error handling during MGCP events
(marked "FIXME"). An upcoming patch implements this error handling, and would
make osmo-msc vulnerable to crash from unexpected MGCP messages without this.

Deferred FSM deallocation is a more general, simpler approach to
osmo_fsm_term_safely(), so we can switch that off now.

Depends: Ief4dba9ea587c9b4aea69993e965fbb20fb80e78 (libosmocore),
         I0adc13a1a998e953b6c850efa2761350dd07e03a (libosmocore)
Related: I7df2e9202b04e7ca7366bb0a8ec53cf3bb14faf3 (osmo-mgw)
Change-Id: I08c03946605aa12e0a5ce8b3c773704ef5327a7a
1 file changed