pwm: Drop two unused API functions

These functions are unused. Also I think there is no valid use case
where these are correct to be called. So drop them.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

include/linux/pwm.h

@@ -111,12 +111,6 @@ static inline bool pwm_is_enabled(const struct pwm_device *pwm)
 	return state.enabled;
 }
 
-static inline void pwm_set_period(struct pwm_device *pwm, u64 period)
-{
-	if (pwm)
-		pwm->state.period = period;
-}
-
 static inline u64 pwm_get_period(const struct pwm_device *pwm)
 {
 	struct pwm_state state;
@@ -126,12 +120,6 @@ static inline u64 pwm_get_period(const struct pwm_device *pwm)
 	return state.period;
 }
 
-static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty)
-{
-	if (pwm)
-		pwm->state.duty_cycle = duty;
-}
-
 static inline u64 pwm_get_duty_cycle(const struct pwm_device *pwm)
 {
 	struct pwm_state state;