sched: Revert nohz_ratelimit() for now

https://lists.ubuntu.com/archives/kernel-team/2010-August/012037.html

Norbert reported that nohz_ratelimit() causes his laptop to burn about
4W (40%) extra. For now back out the change and see if we can adjust
the power management code to make better decisions.

Reported-by: Norbert Preining <preining@logic.at>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
(cherry picked from commit 396e894d289d69bacf5acd983c97cd6e21a14c08 in
git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-tip.git)

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>