staging: unisys: rename variable to reserverd since it is unused

This patch renames send_irq_handle to reserved1 since this variable
is unused in the guest side.

Signed-off-by: Erik Arfvidson <erik.arfvidson@unisys.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>