libselinux - correct selabel invalid context logging

-----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/

iEYEARECAAYFAk7vrQgACgkQrlYvE4MpobNqFwCg1a/hr6EIDZDRRKeB82uDP2I2 ATYAoOfh4Gg3yCnLkLUvWZETac9AbbXI
=Us7a
-----END PGP SIGNATURE-----