Fix previous commit

src/playlist/engine.c

@@ -177,7 +177,7 @@ static void playlist_Destructor( vlc_object_t * p_this )
     if( p_playlist->p_fetcher )
         vlc_object_release( p_playlist->p_fetcher );
 #ifndef NDEBUG
-    p_this->p_libvlc->p_playlist = NULL; /* pl_Yield() will fail */
+    libvlc_priv (p_this->p_libvlc)->p_playlist = NULL; /* pl_Yield() will fail */
 #endif
 }