Add xen hypercall numbers defined for arch specific use.
ia64/xen domU uses __HYPERVISOR_arch_1 to manipulate paravirtualized
IOSAPIC. Although all those constants aren't used yet by IA64 at this
moment, add all arch specific hypercall numbers.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>