We don't need the vlc_mutex_lock here.

src/misc/update.c

@@ -1068,8 +1068,6 @@ void update_Delete( update_t *p_update )
 {
     assert( p_update );
 
-    vlc_mutex_lock( &p_update->lock );
-
     if( p_update->p_check )
     {
         assert( !p_update->p_download );
@@ -1082,7 +1080,6 @@ void update_Delete( update_t *p_update )
         vlc_thread_join( p_update->p_download );
     }
 
-    vlc_mutex_unlock( &p_update->lock );
     vlc_mutex_destroy( &p_update->lock );
 
     free( p_update->release.psz_url );