x86/acpi: store ACPI ids from MADT for future usage

x86/acpi: store ACPI ids from MADT for future usage

Currently we don't save ACPI ids (unlike LAPIC ids which go to
x86_cpu_to_apicid) from MADT and we may need this information later.
Particularly, ACPI ids is the only existent way for a PVHVM Xen guest
to figure out Xen's idea of its vCPUs ids before these CPUs boot and
in some cases these ids diverge from Linux's cpu ids.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
(cherry picked from commit 3e9e57fad3d8530aa30787f861c710f598ddc4e7)
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Orabug: 24820937