[PATCH] x86_64: fix sync before RDTSC on Intel cpus

Commit c818a181 didn't do the expected
thing.  This fix will remove the additional sync(cpuid) before RDTSC on
Intel platforms..

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>