Windows: remove unused variables in fs.c

Windows: remove unused variables in fs.c

Reviewed-on: http://gerrit.openafs.org/5247
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit 578db3bbecf218e3ab80f4896b7cde4d3975daaa)

Change-Id: I8c334239a888d88422ca65d3372228417d60657a
Reviewed-on: http://gerrit.openafs.org/5253
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>