Fixed compiler warning on event_dispatch() as pointed out by Andrew, who wants...

Fixed compiler warning on event_dispatch() as pointed out by Andrew, who wants eternal fame for discovering the problem.

eventlib/c/event

@@ -59,7 +59,7 @@ _kernel_oserror *event_dispatch (int event_code, WimpPollBlock *poll_block)
      * This is mainly required by Java, but could be applicable to
      * other apps...
      */
-    dispatch(event_code, poll_block, event__id_block);
+    return dispatch(event_code, poll_block, event__id_block);
 }