target-i386: Move CPU models from cpus-x86_64.conf to C

target-i386: Move CPU models from cpus-x86_64.conf to C

Those models are maintained by QEMU and may require compatibility code
to be added when making some changes. Keeping the data in the C source
code should make it simpler to handle those details.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Don Slutz <Don@CloudSwitch.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>