ao_pipewire: explicitly remove stream hook

We want to add more logic to the stream event handler.
This logic should not be triggered during normal stream shutdown, so we
remove the listener beforehand.

audio/out/ao_pipewire.c

@@ -280,6 +280,8 @@ static void uninit(struct ao *ao)
     struct priv *p = ao->priv;
     if (p->loop)
         pw_thread_loop_stop(p->loop);
+    spa_hook_remove(&p->stream_listener);
+    spa_zero(p->stream_listener);
     if (p->stream)
         pw_stream_destroy(p->stream);
     p->stream = NULL;