Add support for rejected inference responses

Change-Id: I62e13df69c712ed4cf70766429b4cb13fc9c9dcb
diff --git a/kernel/uapi/ethosu.h b/kernel/uapi/ethosu.h
index fda7fc2..4627cb9 100644
--- a/kernel/uapi/ethosu.h
+++ b/kernel/uapi/ethosu.h
@@ -75,7 +75,9 @@
  */
 enum ethosu_uapi_status {
 	ETHOSU_UAPI_STATUS_OK,
-	ETHOSU_UAPI_STATUS_ERROR
+	ETHOSU_UAPI_STATUS_ERROR,
+	ETHOSU_UAPI_STATUS_RUNNING,
+	ETHOSU_UAPI_STATUS_REJECTED,
 };
 
 /**