x86, uv: update x86 mmr list for SGI uv

This patch updates the X86 mmr list for SGI uv.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Russ Anderson <rja@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>