Fix crash on exit. This resolves bug report 1586.

src/autostart.cpp

@@ -102,8 +102,11 @@ void updateService() {
   if (bisDesktop) service = new KService( fileName.path() );
   }
   ~desktop() {
+    if(service) {
+      service = NULL;
       delete service;
     }
+  }
 };
 
 typedef KGenericFactory<autostart, TQWidget> autostartFactory;