Check for osmo_fsm_register() error return value

Change-Id: I4cce3d6798fe3184a3085d114b749b4645620978
diff --git a/src/libmsc/mncc_call.c b/src/libmsc/mncc_call.c
index e5fc820..0deb903 100644
--- a/src/libmsc/mncc_call.c
+++ b/src/libmsc/mncc_call.c
@@ -60,7 +60,7 @@
 
 void mncc_call_fsm_init(struct gsm_network *net)
 {
-	osmo_fsm_register(&mncc_call_fsm);
+	OSMO_ASSERT(osmo_fsm_register(&mncc_call_fsm) == 0);
 	gsmnet = net;
 }
 
diff --git a/src/libmsc/msc_ho.c b/src/libmsc/msc_ho.c
index 99f37b6..ac7602f 100644
--- a/src/libmsc/msc_ho.c
+++ b/src/libmsc/msc_ho.c
@@ -62,7 +62,7 @@
 
 static __attribute__((constructor)) void msc_ho_fsm_init()
 {
-	osmo_fsm_register(&msc_ho_fsm);
+	OSMO_ASSERT(osmo_fsm_register(&msc_ho_fsm) == 0);
 }
 
 void msc_ho_down_required_reject(struct msc_a *msc_a, enum gsm0808_cause cause)