target/i386: check CPUID_PAE to determine 36 bit processor address space

PAE mode in x86 supports 36 bit address space. Check the PAE CPUID on the
guest processor and set phys_bits to 36 if PAE feature is set. This is in
addition to checking the presence of PSE36 CPUID feature for setting 36 bit
phys_bits.

Signed-off-by: Ani Sinha <anisinha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-ID: <20230912120650.371781-1-anisinha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/cpu.c

@@ -7377,7 +7377,7 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
             return;
         }
 
-        if (env->features[FEAT_1_EDX] & CPUID_PSE36) {
+        if (env->features[FEAT_1_EDX] & (CPUID_PSE36 | CPUID_PAE)) {
             cpu->phys_bits = 36;
         } else {
             cpu->phys_bits = 32;