leds: leds-pwm: drop one pwm_get_period() call

pwm_get_period() is called twice in case the child parameter is set. I
assume retrieving this parameter once is enough therefore this patch
removes the conditial invocation of pwm_get_period().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

drivers/leds/leds-pwm.c

@@ -121,9 +121,6 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
 		return ret;
 	}
 
-	if (child)
-		led_data->period = pwm_get_period(led_data->pwm);
-
 	led_data->can_sleep = pwm_can_sleep(led_data->pwm);
 	if (led_data->can_sleep)
 		INIT_WORK(&led_data->work, led_pwm_work);