Don't require location under track element in xspf-playlist.

Should fix #1597

modules/demux/playlist/xspf.c

@@ -509,14 +509,9 @@ static bool parse_track_node COMPLEX_INTERFACE
                     FREE_ATT();
 
                     if( p_demux->p_sys->i_track_id < 0 )
-                    {
-                        char *psz_uri = input_item_GetURI( p_new_input );
-                        if( psz_uri && *psz_uri)
                     {
                         input_item_AddSubItem( p_input_item, p_new_input );
-                        }
                         vlc_gc_decref( p_new_input );
-                        free( psz_uri );
                         return true;
                     }