[IA64] Add dp bit to cache and bus check structs

Rev 2.2 of Volume 2 of "Intel Itanium Architecture Software Developer's
Manual" (January 2006) adds a dp bit to the cache_check and bus_check
fields (pages 2:401-2:404).  This patch gets the structs back in sync
with the spec.

Signed-off-by: Russ Anderson <(rja@sgi.com)>
Signed-off-by: Tony Luck <tony.luck@intel.com>