[PATCH] x86_64: Fix NMI watchdog on x460

[description from AK]

Old check for the IO-APIC watchdog during the timer check was wrong -
it obviously should only drop into this if the IO-APIC watchdog is used.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>