Windows: Add trace to track setting VERIFY flag

Add trace statements at each location the VERIFY flag is set or
cleared.

Reviewed-on: http://gerrit.openafs.org/10216
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit 7c8eb2f2288706a75fda67acae52a5b89dc8343f)

Change-Id: Id1ebf51173857f671e855465b9bd345cf7b8c6ca
Reviewed-on: http://gerrit.openafs.org/10221
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>