tests/readlink.py

rust-utils: use new find_dirs iterator

In cad3dde7a573, the `find_dirs` util was introduced, but the second changeset
that made use of it didn't apply. This change fixes the issue.

Differential Revision: https://phab.mercurial-scm.org/D6639

#!/usr/bin/env python

from __future__ import absolute_import, print_function

import errno
import os
import sys

for f in sys.argv[1:]:
    try:
        print(f, '->', os.readlink(f))
    except OSError as err:
        if err.errno != errno.EINVAL:
            raise
        print(f, '->', f, 'not a symlink')

sys.exit(0)