PCI: Make sure hotplug ioapic driver get loaded early

at least before port service.

Some system MADT will only have no hotplug entries even those devices are
there before os is booting.

So we need to enable those ioapic early before real device driver need to
setup ioapic irq.

Also need to make it depends on X86_IO_APIC.

Signed-off-by: <yinghai@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>