target-i386: Use uint32_t for X86CPU.apic_id

target-i386: Use uint32_t for X86CPU.apic_id

Redo 9886e834 (target-i386: Require APIC ID to be explicitly set before
CPU realize) in another way that doesn't use int64_t to detect
if apic-id property has been set.

Use the fact that 0xFFFFFFFF is the broadcast
value that a CPU can't have and set default
uint32_t apic_id to it instead of using int64_t.

Later uint32_t apic_id will be used to drop custom
property setter/getter in favor of static property.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>