cgroup: Take css_set_lock from cgroup_css_sets_empty()

Conflicts:
	kernel/cgroup.c
cgroup: Fix use after free of cgrp (cgrp->css_sets)
msm-sleeper: limit max freq when screen is off
msm-sleeper: disable messages

Signed-off-by: flar2 <asegaert@gmail.com>
defconfig: msm_sleeper

Conflicts:
	arch/arm/configs/m7_defconfig
msm-sleeper: add ex_max_freq interface