leds: mt6323: Get rid of custom led_init_default_state_get()

LED core provides a helper to parse default state from firmware node.
Use it instead of custom implementation.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230103131256.33894-7-andriy.shevchenko@linux.intel.com

drivers/leds/leds-mt6323.c

@@ -339,23 +339,23 @@ static int mt6323_led_set_dt_default(struct led_classdev *cdev,
 				     struct device_node *np)
 {
 	struct mt6323_led *led = container_of(cdev, struct mt6323_led, cdev);
-	const char *state;
+	enum led_default_state state;
 	int ret = 0;
 
-	state = of_get_property(np, "default-state", NULL);
-	if (state) {
-		if (!strcmp(state, "keep")) {
-			ret = mt6323_get_led_hw_brightness(cdev);
-			if (ret < 0)
-				return ret;
-			led->current_brightness = ret;
-			ret = 0;
-		} else if (!strcmp(state, "on")) {
-			ret =
-			mt6323_led_set_brightness(cdev, cdev->max_brightness);
-		} else  {
-			ret = mt6323_led_set_brightness(cdev, LED_OFF);
-		}
+	state = led_init_default_state_get(of_fwnode_handle(np));
+	switch (state) {
+	case LEDS_DEFSTATE_ON:
+		ret = mt6323_led_set_brightness(cdev, cdev->max_brightness);
+		break;
+	case LEDS_DEFSTATE_KEEP:
+		ret = mt6323_get_led_hw_brightness(cdev);
+		if (ret < 0)
+			return ret;
+		led->current_brightness = ret;
+		ret = 0;
+		break;
+	default:
+		ret = mt6323_led_set_brightness(cdev, LED_OFF);
 	}
 
 	return ret;