x86: cacheinfo: use cached K8 NB_MISC devices instead of scanning for it

Impact: avoid code duplication

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Langsdorf <mark.langsdorf@amd.com>
LKML-Reference: <20090409131617.GI31527@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>