Avoid static analysis warnings

src/datawizard/datawizard.c

@@ -69,7 +69,7 @@ int __starpu_datawizard_progress(unsigned may_alloc, unsigned push_requests)
         int current_worker_id = starpu_worker_get_id();
         unsigned memnode;
 
-	if (current_worker_id == -1)
+	if (current_worker_id < 0)
 		/* Call from main application, only make RAM requests progress */
 		return ___starpu_datawizard_progress(STARPU_MAIN_RAM, may_alloc, push_requests);