As spotted by one of our Fedora users, we sometimes
oops during shutdown (http://www.roberthancock.com/kerneloops.png)
because disable_IO_APIC() wants to call find_isa_irq_pin(),
which we threw away during init.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>