i386: Introduce use_epyc_apic_id_encoding in X86CPUDefinition

i386: Introduce use_epyc_apic_id_encoding in X86CPUDefinition

Add a boolean variable use_epyc_apic_id_encoding in X86CPUDefinition.
This will be set if this cpu model needs to use new EPYC based
apic id encoding.

Override the handlers with EPYC based handlers if use_epyc_apic_id_encoding
is set. This will be done in x86_cpus_init.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Message-Id: <158396723514.58170.14825482171652019765.stgit@naples-babu.amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>