cpufreq: make thermald play nicely with OC
GPU 3D: Overclock: Add 480Mhz slot - controllable via sysfs

/sys/devices/platform/kgsl-3d0.0/kgsl/kgsl-3d0/max_pwrlevel

0 = Enable 480Mhz slot
1 = Disable 480Mhz slot (keep max at 400Mhz)

max_gpuclk also works.

Change-Id: I55eb92bd72000966d11fcfbece659e20bebae0d5
set 480mhz as default gpu clock
stable 1.8ghz oc???