i386: use better matching family/model/stepping for 'qemu64' CPU

i386: use better matching family/model/stepping for 'qemu64' CPU

The 'qemu64' CPUID currently reports a family/model/stepping that
approximately corresponds to an AMD K7 vintage architecture.
The K7 series predates the introduction of 64-bit support by AMD
in the K8 series. This has been reported to lead to LLVM complaints
about generating 64-bit code for a 32-bit CPU target

  LLVM ERROR: 64-bit code requested on a subtarget that doesn't support it!

It appears LLVM looks at the family/model/stepping, despite qemu64
reporting it is 64-bit capable.

This patch changes 'qemu64' to report a CPUID with the family, model
and stepping taken from a

 AMD Athlon(tm) 64 X2 Dual Core Processor 4000+

which is one of the first 64-bit AMD CPUs.

Closes https://gitlab.com/qemu-project/qemu/-/issues/191

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20210507133650.645526-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>