x86, uv, uv3: Update x2apic Support for SGI UV3

x86, uv, uv3: Update x2apic Support for SGI UV3

This patch adds support for the SGI UV3 hub to the common x2apic
functions.  The primary changes are to account for the similarities
between UV2 and UV3 which are encompassed within the "UVX" nomenclature.

One significant difference within UV3 is the handling of the MMIOH
regions which are redirected to the target blade (with the device) in
a different manner.  It also now has two MMIOH regions for both small and
large BARs.  This aids in limiting the amount of physical address space
removed from real memory that's used for I/O in the max config of 64TB.

Signed-off-by: Mike Travis <travis@sgi.com>
Link: http://lkml.kernel.org/r/20130211194508.752924185@gulag1.americas.sgi.com
Acked-by: Russ Anderson <rja@sgi.com>
Reviewed-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Steffen Persvold <sp@numascale.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>