Windows: Hold Fcb Resource across CcPurgeSection

Windows: Hold Fcb Resource across CcPurgeSection

Now that the Fcb Resource and SectionObjectResource are held in
the FastIo pathway and the Trend Micro deadlock has been addressed
by holding a reference on the FileObject it is time to fix the
lock acquisition ordering.   For each CcPurgeSection call the
Fcb Resource will be held exclusive before the SectionObjectResource.

Change-Id: Ica9e3674b39e2789c35bcf13d9fa1f2326420119
Reviewed-on: http://gerrit.openafs.org/10192
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>