kernel: cgroup: protecting css_set object

Accessing the css_set object should be protected with css_set_lock.
NULL check is required before accesing object.

CRs-fixed: 723762
Change-Id: Ia3a0314a04419889d5002a8f2bf2c1fe9dfa3671
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>

I have this Commit already:
https://github.com/dorimanx/Dorimanx-LG-G2-D802-Kernel/commit/57603bba0f773fc3ea7e7b331710eaa2e5bb957b

so i have just merged the cg && check, from this commit
https://www.codeaurora.org/cgit/quic/la/kernel/msm/commit/?h=kk_3.5&id=4ac97cf6dc2fb87017a51ae533b932f5a2013c9f
build: Use hard-float abi 2
update version to 89u-r9