pwm: lpss: Add support for runtime PM

To be able to save some power when PWM is not in use, add support for
runtime PM for this driver. This also allows the platform to transition to
low power S0ix states when the system is idle.

Signed-off-by: Huiquan Zhong <[email protected]>
Signed-off-by: Qipeng Zha <[email protected]>
Signed-off-by: Mika Westerberg <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
3 files changed