MT#57719 Use media subscriptions approach in `stream_packet()`

Start using the media subscriptions model
(based on newly introduced `media_subscription` objects)
in scope of `stream_packet()`.

Change-Id: Ia8d9442810c4afc12b00cad8b1a354d66bb5051c

daemon/media_socket.c

@@ -3061,19 +3061,25 @@ out:
 		unconfirm_sinks(&phc->mp.stream->rtcp_sinks, "peer address unconfirmed");
 	}
 	if (phc->unkernelize_subscriptions) {
-		// XXX optimise this triple loop?
-		for (GList *l = phc->mp.media->monologue->subscriptions.head; l; l = l->next) {
-			struct call_subscription *cs = l->data;
-			struct call_monologue *sub = cs->monologue;
-			for (unsigned int k = 0; k < sub->medias->len; k++) {
-				struct call_media *sub_media = sub->medias->pdata[k];
+		AUTO_CLEANUP(GQueue mls, g_queue_clear) = G_QUEUE_INIT; /* to avoid duplications */
+		for (GList * sub = phc->mp.media->media_subscriptions.head; sub; sub = sub->next)
+		{
+			struct media_subscription * ms = sub->data;
+
+			if (!g_queue_find(&mls, ms->monologue)) {
+				for (unsigned int k = 0; k < ms->monologue->medias->len; k++)
+				{
+					struct call_media *sub_media = ms->monologue->medias->pdata[k];
 					if (!sub_media)
 						continue;
+
 					for (GList *m = sub_media->streams.head; m; m = m->next) {
 						struct packet_stream *sub_ps = m->data;
 						__unkernelize(sub_ps, "subscriptions modified");
 					}
 				}
+				g_queue_push_tail(&mls, ms->monologue);
+			}
 		}
 	}