Windows: avoid deadlock with Trend Micro

Windows: avoid deadlock with Trend Micro

Trend Micro's anti-virus driver attempts to open the file in
response to CcPurgeCacheSection().  While processing
AFSSetDispositionInfo() the Fcb->NPFcb->Resource is held which is
also required if a status verification is required during the
CreateFile operation.  That results in a deadlock.

Avoid the deadlock by setting the PENDING_DELETE flag prior to
calling CcPurgeCacheSection().

Change-Id: I40d93d70e120525343afb917d473ad79a1f36e29
Reviewed-on: http://gerrit.openafs.org/6988
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>