Originally suggested by Zwane Mwaikumbo

Ignore all ACPI timer overrides on all Nvidia boards.  The fallback doesn't
work and no Nvidia boards needs a timer override.  But some buggy BIOS have
it anyways.

Also enable IO-APIC mode by default for Nvidia then.

Thanks to Andy Currid for confirming this.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>