Impact: fix wakeup_secondary_cpu with hotplug

We can not put that into x86_quirks, because that is __initdata.
So try to move that to genapic, and add update_genapic in x86_quirks.

later we even could use that stub to:

 1. autodetect CONFIG_ES7000_CLUSTERED_APIC
 2. more correct inquire_remote_apic with apic_verbosity setting.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>