player: drop the enhancement-layer pairing when the media has no EL

demux/stheader.h

@@ -112,7 +112,7 @@ static inline struct sh_stream *sh_stream_dependent_sibling(struct sh_stream *bl
     for (int i = 0; i < bl->group->num_members; i++) {
         struct sh_stream *m = bl->group->members[i];
         if (m && m != bl && m->dependent_track && m->type == bl->type)
-            return m;
+            return m->absent ? NULL : m;
     }
     return NULL;
 }

player/playloop.c

@@ -1289,6 +1289,8 @@ void run_playloop(struct MPContext *mpctx)
 
     update_sparse_video(mpctx);
 
+    update_vo_chain_el_pair(mpctx);
+
     handle_cursor_autohide(mpctx);
     handle_vo_events(mpctx);
     handle_command_updates(mpctx);