Merge branch 'rs/no-mode-to-open-when-appending' into maint

The "mode" word is useless in a call to open(2) that does not
create a new file.  Such a call in the files backend of the ref
subsystem has been cleaned up.

* rs/no-mode-to-open-when-appending:
  refs/files-backend: remove unused open mode parameter

refs/files-backend.c

@@ -1569,7 +1569,7 @@ static int log_ref_setup(struct files_ref_store *refs,
 			goto error;
 		}
 	} else {
-		*logfd = open(logfile, O_APPEND | O_WRONLY, 0666);
+		*logfd = open(logfile, O_APPEND | O_WRONLY);
 		if (*logfd < 0) {
 			if (errno == ENOENT || errno == EISDIR) {
 				/*