fix a bug for err logger

internal/appchain/port.go

@@ -83,7 +83,7 @@ func (a *appChain) AsyncSend(msg *pb.Message) error {
 			return err
 		}
 		if ibtp == nil {
-			return errors.New("ibtp wrong")
+			return nil
 		}
 	}
 	return errors.New("ibtp type wrong")