src: use namespace prefix osmo_signal*

Summary of changes:

s/signal_cbfn/osmo_signal_cbfn/g
s/register_signal_handler/osmo_signal_register_handler/g
s/unregister_signal_handler/osmo_signal_unregister_handler/g
s/dispatch_signal/osmo_signal_dispatch/g
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_audio.c b/openbsc/src/osmo-bsc/osmo_bsc_audio.c
index 515cfa7..64260aa 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_audio.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_audio.c
@@ -65,6 +65,6 @@
 int osmo_bsc_audio_init(struct gsm_network *net)
 {
 	net->hardcoded_rtp_payload = 98;
-	register_signal_handler(SS_ABISIP, handle_abisip_signal, net);
+	osmo_signal_register_handler(SS_ABISIP, handle_abisip_signal, net);
 	return 0;
 }
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_grace.c b/openbsc/src/osmo-bsc/osmo_bsc_grace.c
index f699cf3..c67984b 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_grace.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_grace.c
@@ -103,5 +103,5 @@
 
 static __attribute__((constructor)) void on_dso_load_grace(void)
 {
-	register_signal_handler(SS_RF, handle_rf_signal, NULL);
+	osmo_signal_register_handler(SS_RF, handle_rf_signal, NULL);
 }
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_main.c b/openbsc/src/osmo-bsc/osmo_bsc_main.c
index 6437d93..78a0ccb 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_main.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_main.c
@@ -149,7 +149,7 @@
 	switch (signal) {
 	case SIGINT:
 		bsc_shutdown_net(bsc_gsmnet);
-		dispatch_signal(SS_GLOBAL, S_GLOBAL_SHUTDOWN, NULL);
+		osmo_signal_dispatch(SS_GLOBAL, S_GLOBAL_SHUTDOWN, NULL);
 		sleep(3);
 		exit(0);
 		break;
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_msc.c b/openbsc/src/osmo-bsc/osmo_bsc_msc.c
index 8b7c6e2..b4feded 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_msc.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_msc.c
@@ -306,7 +306,7 @@
 	msc_ping_timeout_cb(data);
 
 	sig.data = data;
-	dispatch_signal(SS_MSC, S_MSC_CONNECTED, &sig);
+	osmo_signal_dispatch(SS_MSC, S_MSC_CONNECTED, &sig);
 }
 
 /*
@@ -325,7 +325,7 @@
 	osmo_timer_del(&data->pong_timer);
 
 	sig.data = data;
-	dispatch_signal(SS_MSC, S_MSC_LOST, &sig);
+	osmo_signal_dispatch(SS_MSC, S_MSC_LOST, &sig);
 
 	msc->is_authenticated = 0;
 	bsc_msc_schedule_connect(msc);
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_rf.c b/openbsc/src/osmo-bsc/osmo_bsc_rf.c
index 5ce6bf5..78550d7 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_rf.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_rf.c
@@ -137,7 +137,7 @@
 	sig.net = rf->gsm_network;
 
 	rf->policy = val;
-	dispatch_signal(SS_RF, val, &sig);
+	osmo_signal_dispatch(SS_RF, val, &sig);
 }
 
 static int switch_rf_off(struct osmo_bsc_rf *rf)
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_sccp.c b/openbsc/src/osmo-bsc/osmo_bsc_sccp.c
index 099552b..f4cdf36 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_sccp.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_sccp.c
@@ -282,7 +282,7 @@
 	sccp_connection_set_incoming(&sccp_ssn_bssap, msc_sccp_accept, NULL);
 	sccp_set_read(&sccp_ssn_bssap, msc_sccp_read, gsmnet);
 
-	register_signal_handler(SS_MSC, handle_msc_signal, gsmnet);
+	osmo_signal_register_handler(SS_MSC, handle_msc_signal, gsmnet);
 
 	return 0;
 }