policycoreutils: po: Makefile use -p to preserve times

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

This patch looks good to me. acked.

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAk7dHFAACgkQrlYvE4MpobNgbQCgk9PDPTxstdQWhibMfVN/Z1kh AfsAoIahnMVjUNbxH7XATu9O1fVb7tEP
=OfT9
-----END PGP SIGNATURE-----