Revert "cpuset: Fix allow_attach hook for cpusets on android."

This reverts commit 03d7df80.

Part of Chromium commit series:

CHROMIUM: remove Android's cgroup generic permissions checks

The implementation is utterly broken, resulting in all processes being
allows to move tasks between sets (as long as they have access to the
"tasks" attribute), and upstream is heading towards checking only
capability anyway, so let's get rid of this code.

BUG=b:31790445,chromium:647994
TEST=Boot android container, examine logcat

Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/394967


Reviewed-by: Ricky Zhou <rickyz@chromium.org>
Reviewed-by: John Stultz <john.stultz@linaro.org>

Change-Id: I888a882931909d1039024198b465ec2ffcd619ec
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>