i386/cpu: Drop the variable smp_cores and smp_threads in x86_cpu_pre_plug()

i386/cpu: Drop the variable smp_cores and smp_threads in x86_cpu_pre_plug()

No need to define smp_cores and smp_threads, just using ms->smp.cores
and ms->smp.threads is straightforward. It's also consistent with other
checks of socket/die/module.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20241219110125.1266461-3-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>