Don't force the whole-file option when using read-batch.

generator.c

@@ -213,7 +213,7 @@ static BOOL disable_deltas_p(void)
 {
 	if (whole_file > 0)
 		return True;
-	if (whole_file == 0 || write_batch)
+	if (whole_file == 0 || write_batch || read_batch)
 		return False;
 	return local_server;
 }