macosx: Add a missing PL_LOCK in the wizard.

modules/gui/macosx/wizard.m

@@ -1299,9 +1299,11 @@ static VLCWizard *_o_sharedInstance = nil;
             if( x == 0 )
             {
                 /* play the first item and add the others afterwards */
+                PL_LOCK;
                 playlist_item_t *p_item = playlist_ItemGetByInput( p_playlist, p_input, pl_Locked );
-                playlist_Control( p_playlist, PLAYLIST_VIEWPLAY, true, NULL,
+                playlist_Control( p_playlist, PLAYLIST_VIEWPLAY, pl_Locked, NULL,
                           p_item );
+                PL_UNLOCK;
             }
 
             vlc_gc_decref( p_input );