Windows: Increase AFS DeviceObject StackSize

Increase the StackSize parameter of the DeviceObjects allocated
by the AFS Redirector framework.  The StackSize parameter is used
to notify callers how many Irp Stack frames will be consumed.  Now
that the redirector is using IoCompletion routines, an additional
stack frame is required to handle calls to the AFS Redirector library
driver.

Thanks to Peter Scott for identifying the solution.

FIXES 131618

Change-Id: Ib66f884911f0d425e6e07f338a36b3ebedeb8871
Reviewed-on: http://gerrit.openafs.org/9609
Reviewed-by: Peter Scott <pscott@kerneldrivers.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Rod Widdowson <rdw@steadingsoftware.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>
Tested-by: Jeffrey Altman <jaltman@your-file-system.com>