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.

Depends: Ief4dba9ea587c9b4aea69993e965fbb20fb80e78 (libosmocore),
         I0adc13a1a998e953b6c850efa2761350dd07e03a (libosmocore)
Related: I7df2e9202b04e7ca7366bb0a8ec53cf3bb14faf3 (osmo-mgw)
Change-Id: Ib7fce7b7d54dfb87af97544796680919e5929a50

src/osmo-bsc/osmo_bsc_main.c

@@ -821,6 +821,8 @@ int main(int argc, char **argv)
 	osmo_stats_init(tall_bsc_ctx);
 	rate_ctr_init(tall_bsc_ctx);
 
+	osmo_fsm_set_dealloc_ctx(OTC_SELECT);
+
 	/* Allocate global gsm_network struct */
 	rc = bsc_network_alloc();
 	if (rc) {
@@ -939,7 +941,7 @@ int main(int argc, char **argv)
 	}
 
 	while (1) {
-		osmo_select_main(0);
+		osmo_select_main_ctx(0);
 	}
 
 	return 0;