[IA64] fixes configs and add default config for ia64 xen domU

This patch fixes xen related Kconfigs and add default config
file for ia64 xen domU.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
3 files changed