Windows: Claim success for Delete Reparse Tag

The typical pattern for deleting a reparse point is

 1. open reparse point object
 2. delete reparse tag
 3. set delete on close
 4. close handle

Claim success when we receive delete reparse tag fsctl so that
the delete on close disposition can be set.

Change-Id: I8f4212dd6ba04be95455eaa210e632ca59cfa7c8
Reviewed-on: http://gerrit.openafs.org/9427
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>