i386/hvf: Make CPUID_HT supported

i386/hvf: Make CPUID_HT supported

Since Commit c6bd2dd63420 ("i386/cpu: Set up CPUID_HT in
x86_cpu_expand_features() instead of cpu_x86_cpuid()"), CPUID_HT will be
set in env->features[] in x86_cpu_expand_features() when vcpus >= 2.

Later in x86_cpu_filter_features() it will check against the HVF
supported bits. It will trigger the warning like

    qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.01H:EDX.ht [bit 28]

Add CPUID_HT to HVF supported CPUID bits to fix it.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20250514031652.838763-3-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>