x86/sched: Remove SD_ASYM_PACKING from the SMT domain flags

There is no difference between any of the SMT siblings of a physical core.
Do not do asym_packing load balancing at this level.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20230406203148.19182-11-ricardo.neri-calderon@linux.intel.com