aklog: Search for /etc/krb5/krb5.conf

aklog tweaks the KRB5_CONFIG environment var when performing one of
our 'weak crypto' workarounds. We assume that the default krb5.conf is
/etc/krb5.conf, but for Solaris 11 libkrb5, krb5.conf is in
/etc/krb5/krb5.conf. Although this file could be anywhere, try
/etc/krb5/krb5.conf too, so we at least work on stock Solaris.

Reviewed-on: http://gerrit.openafs.org/9666
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit cd1ffc1073d6f9a191e07cb72e8d0b4ec8cd6347)

Change-Id: I8eeb406107592bac6da415d25b688d936a385a87
Reviewed-on: http://gerrit.openafs.org/9686
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>