osx: deal with more kerberos damage

osx: deal with more kerberos damage

the number of things which can return success without succeeding is
truly sad.

Reviewed-on: http://gerrit.openafs.org/6911
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit 59b57ff85acbef10bcec9724c42e3bad78538687)

Change-Id: Ie41cb88f9b58945b8ae486eab671b00fe0cf10a6
Reviewed-on: http://gerrit.openafs.org/6964
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: Derrick Brashear <shadow@dementix.org>