staging: unisys: fix kdump support

The s-Par drivers used to be out-of-tree, so they needed a parameter to
let them know we were going into a dump. This patch removes that code
and uses the built-in kernel function instead.

Reviewed-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>