[IA64-SGI] - New SN hardware support - addr_macros

Update the SN address macros so that they work on both shub1 
and shub2. Most of the code to support shub2 was added last year
but this patch fixes a few bugs and adds macros to help generate
both processor-specific physical addresses & numalink physical
addresses. More cleanup & optimization will be done later.


Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>