ws2401: add thread to update APE_OPP

Signed-off-by: Shilin Victor <chrono.monochrome@gmail.com>
ws2401: add interface to control min APE/DDR on screen on

Signed-off-by: Shilin Victor <chrono.monochrome@gmail.com>
mali: ux500: re-add mali_opp interface

Signed-off-by: Shilin Victor <chrono.monochrome@gmail.com>