Windows: AFSValidateEntry Symlink TargetName

Windows: AFSValidateEntry Symlink TargetName

During an AFSValidateEntry if the data version of the symlink
object has not changed, do not discard or rebuild the target
name if already assisgned.

Change-Id: If37af308ee48ec761283ff6e831ffa5e06dacf58
Reviewed-on: http://gerrit.openafs.org/8515
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>