target-i386: emulate CPUID level of real hardware

W10 insider has a bug where it ignores CPUID level and interprets
CPUID.(EAX=07H, ECX=0H) incorrectly, because CPUID in fact returned
CPUID.(EAX=04H, ECX=0H);  this resulted in execution of unsupported
instructions.

While it's a Windows bug, there is no reason to emulate incorrect level.

I used http://instlatx64.atw.hu/

 as a source of CPUID and checked that
it matches Penryn Xeon X5472, Westmere Xeon W3520, SandyBridge i5-2540M,
and Haswell i5-4670T.

kvm64 and qemu64 were bumped to 0xD to allow all available features for
them (and to avoid the same Windows bug).

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>