Windows: AFSPerformObjectInvalidate FILE processing

Refactor AFSPerformObjectInvalidate so that all of the non-DIRECT_IO
processing variables are in the Extents processing section.  Remove
all references to Extents processing from the DIRECT_IO block.

Reviewed-on: http://gerrit.openafs.org/10188
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
(cherry picked from commit cb53d414bbc4ecaf1b136b4a3c82bea3cc9044b6)

Change-Id: I570e18e19dfd14e8ed244e2ef71c343d817ed72c
Reviewed-on: http://gerrit.openafs.org/10208
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>