i386/cpu: Consolidate the use of topo_info in cpu_x86_cpuid()

i386/cpu: Consolidate the use of topo_info in cpu_x86_cpuid()

In cpu_x86_cpuid(), there are many variables in representing the cpu
topology, e.g., topo_info, cs->nr_cores and cs->nr_threads.

Since the names of cs->nr_cores and cs->nr_threads do not accurately
represent its meaning, the use of cs->nr_cores or cs->nr_threads is
prone to confusion and mistakes.

And the structure X86CPUTopoInfo names its members clearly, thus the
variable "topo_info" should be preferred.

In addition, in cpu_x86_cpuid(), to uniformly use the topology variable,
replace env->dies with topo_info.dies_per_pkg as well.

Suggested-by: Robert Hoo <robert.hu@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Babu Moger <babu.moger@amd.com>
Message-ID: <20240424154929.1487382-9-zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>