[IA64] pvops: introduce pv_info which describes some random info.

introduce pv_info which describes some randome info about
underlying execution environment.

Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>