Windows: AFS_INVALIDATE_DELETE must cancel IO

Windows: AFS_INVALIDATE_DELETE must cancel IO

When processing an AFS_INVALIDATE_DELETE the redirector
must cancel any outstanding extent requests on the file
prior to tearing down the extents.

This code path is triggered either when VNOVNODE is received
from a file server or when an alternate cache manager interface
(SMB) unlinks the file.

Change-Id: I16c08c2469228b33ae4ece0e45a9890a057ab257
Reviewed-on: http://gerrit.openafs.org/8206
Reviewed-by: Rod Widdowson <rdw@steadingsoftware.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>