GPU Simple Governor: adapt GPU Simple Governor for Snapdrgaon 800 SOCs

initial coding for a Simple GPU governor based on my own work 2 years ago
from Sensation GB kernel commit: c1ea8f6

Signed-off-by: Paul Reioux <reioux@gmail.com>

Conflicts:
	drivers/gpu/msm/kgsl_pwrscale_trustzone.c

Change-Id: Iecf8fc2a7f2740532b019e44580ebd6a3ebe6950
Enable GPU simple govvernor in cyanogen_hammerhead_defconfig

Change-Id: I263f40a04efcab6e3dd11be45fa8eebf3ce0fc40