cgroups: timer_slack: backport to 2.6.32

http://lwn.net/Articles/431847/

This implements the timer slack controller with all needed
patches. To make this actually work with Android
the following is needed in the ramdisk;

	mount cgroup none /dev/cpuctl cpu,timer_slack

I also recommend to set timer_slack.min_slack_ns at boot;

	write /dev/cpuctl/apps/bg_non_interactive/timer_slack.min_slack_ns 100000000

Normally you would mount the controller to change the timer slack,
unfortunately this ist broken at the moment at least for me.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Signed-off-by: Blechd0se <alex.christ@hotmail.de>

Conflicts:
	include/linux/cgroup_subsys.h
	include/linux/prctl.h
shrinker: fix those stupid warnings

We won't use the new shrinker api any time soon, so
go one step back and get rid of those warnings.

Also enable the new timer slack controller for CM10 too.

Signed-off-by: Blechd0se <alex.christ@hotmail.de>