This reverts commit fbdcf18d.

As pointed out by Yanmin Zhang, the problem was already fixed
differently (and correctly), and rather than fix anything, it actually
causes us to create a sub-optimal sched-domains hierarchy (not setting
up the domain belonging to the core) when CONFIG_X86_HT=y.
Requested-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>