Disable acpi build for isapc and no_kvmclock machine
types (used by xen), since acpi build currently expects pci.
Reported-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>