[PATCH] x86: don't use cpuid.2 to determine cache info if cpuid.4 is supported

Don't use cpuid.2 to determine cache info if cpuid.4 is supported.  The
exception is P4 trace cache.  We always use cpuid.2 to get trace cache
under P4.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>