Fix the Intel cache detection code assumption that number of threads
sharing the cache will either be equal to number of HT or core siblings.

This also cleans up the code in general a bit.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>