Windows: AFSClose remove dead code

Change-Id: Ia844d7e01bcf7a04a7115416e83d45bf5319d739
Reviewed-on: http://gerrit.openafs.org/9889
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>