Windows: AFS_INVALIDATE_DATA_VERSION only by service

Let the service make all decisions regarding when a data version
invalidation should be initiated.  If during directory enumeration
or entry validation a data version change is noticed, that is an
indication that the meta data should be updated.

Change-Id: I8872fb5500b08ef2c6b64ab5fd13beeee4267aa2
Reviewed-on: http://gerrit.openafs.org/9743
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Windows: DirectIO AFS_INVALIDATE_DATA_VERSION

Implement cache flush and purge operations in response to
AFS_INVALIDATE_DATA_VERSION requests when DirectIO processing is in use.

Change-Id: Ib97b1ecd0d9f65b8648f2d7d01ee7043d6be2b83
Reviewed-on: http://gerrit.openafs.org/9744
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>