Windows: log FSCTL_CSC_INTERNAL requests

Windows: log FSCTL_CSC_INTERNAL requests

FSCTL_CSC_INTERNAL requests are not supported and will
return STATUS_INVALID_DEVICE_REQUEST.  However, log them
for easier debugging.

FSCTL_CSC_INTERNAL is defined in ntifs.h only for
Vista and above.  Since afsredir is built for XP
and above its value must be conditionally defined
by us.

Change-Id: I39cf1f9d068d28ab6c9267c302d49feece6af700
Reviewed-on: http://gerrit.openafs.org/5773
Reviewed-by: Rod Widdowson <rdw@steadingsoftware.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>