KGSL: Add a simple GPU governor for Adreno xxx GPU series

initial coding for a Simple GPU governor based on my own work 2 years ago
from Sensation GB kernel commit: c1ea8f64167270d67915b4d4fb00910b1c0f513f

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>

Conflicts:

	drivers/gpu/msm/kgsl_pwrscale_trustzone.c

Change-Id: I31ea6b750ce1cbfb8b5c750a72c0b6b9561e2a99
KGSL: make simple govenor a selectable option, co-exist with ondemand

also removed some hardcoded values

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>

Conflicts:

	drivers/gpu/msm/kgsl_pwrscale_trustzone.c

Change-Id: I0b56962957ecedea8ea62d2c45c19e9546efac4d
KGSL: simple governor: expose tunables to sysfs interface via module_param

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
KGSL: Simple Governor: fix minor logic issue

Signed-off-by: Paul Reioux <reioux@gmail.com>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
fix: busclock gpu oc
gpu: add 48mhz step
fix: gpu: 48mhz step
defconfig set CONFIG_MSM_KGSL_SIMPLE_GOV=y

Change-Id: Idf6990b3371149b18e3bdd27e8f6c56c2725fcca
KGSL: Simple Governor: some styling changes, early returns instead of assigning a val and returning in the end of the function call and change the copyright/author from the middle of the file to the header.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>