pwm: crc: Simplify code to determine the pwmchip's parent device

There is already a pointer to the pwmchip, make use of it directly
instead of using the struct crystalcove_pwm *crc_pwm just obtained from
it. This also has the advantage of not using struct
crystalcove_pwm::chip any more which will be dropped soon.

Link: https://lore.kernel.org/r/66d55649e13526bbd95d7bfd1cacfa0beb9efd43.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-crc.c

@@ -55,7 +55,7 @@ static int crc_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 			 const struct pwm_state *state)
 {
 	struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip);
-	struct device *dev = crc_pwm->chip.dev;
+	struct device *dev = chip->dev;
 	int err;
 
 	if (state->period > PWM_MAX_PERIOD_NS) {
@@ -125,7 +125,7 @@ static int crc_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 			     struct pwm_state *state)
 {
 	struct crystalcove_pwm *crc_pwm = to_crc_pwm(chip);
-	struct device *dev = crc_pwm->chip.dev;
+	struct device *dev = chip->dev;
 	unsigned int clk_div, clk_div_reg, duty_cycle_reg;
 	int error;