afsd: Remove unused definitions

Remove some #defines for s_host and similar things. They are not used
anywhere, and they can cause warnings for e.g. s_host being redefined.

Reviewed-on: http://gerrit.openafs.org/3364
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit be6fb658fe717469470bcd28c46bee1901c4d96c)

Change-Id: I9ca3c81dde7321928c96a80ae46ff9b736c1040e
Reviewed-on: http://gerrit.openafs.org/9413
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Tested-by: Stephan Wiesand <stephan.wiesand@desy.de>