pwm: twl: Use to_twl() instead of container_of()

Always use to_twl() for converting into private data instead of
container_of().
Signed-off-by: Johannes Thumshirn <morbidrsa@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

drivers/pwm/pwm-twl.c

@@ -200,8 +200,7 @@ static int twl4030_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-	struct twl_pwm_chip *twl = container_of(chip, struct twl_pwm_chip,
-						chip);
+	struct twl_pwm_chip *twl = to_twl(chip);
 	int ret;
 	u8 val, mask;
 
@@ -231,8 +230,7 @@ static void twl4030_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-	struct twl_pwm_chip *twl = container_of(chip, struct twl_pwm_chip,
-						chip);
+	struct twl_pwm_chip *twl = to_twl(chip);
 	int ret;
 	u8 val;
 
@@ -255,8 +253,7 @@ static int twl6030_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static void twl6030_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-	struct twl_pwm_chip *twl = container_of(chip, struct twl_pwm_chip,
-						chip);
+	struct twl_pwm_chip *twl = to_twl(chip);
 	int ret;
 	u8 val;