Windows: Initialize Irp->IoStatus.Information earlier

Windows: Initialize Irp->IoStatus.Information earlier

Initialize Irp->IoStatus.Information to zero immediately upon
beginning processing of the IRP in the write path.

Change-Id: I8d5a717ae8cd3bc44c2a9a65b34fd0549862d293
Reviewed-on: http://gerrit.openafs.org/9128
Reviewed-by: Rod Widdowson <rdw@steadingsoftware.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>