leds-lp55xx: fix error condition in lp55xx_register_leds()

 Use lp55xx_unregister_leds() rather than duplicate code.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

drivers/leds/leds-lp55xx-common.c

@@ -344,11 +344,7 @@ int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
 	return 0;
 
 err_init_led:
-	for (i = 0; i < chip->num_leds; i++) {
-		each = led + i;
-		led_classdev_unregister(&each->cdev);
-		flush_work(&each->brightness_work);
-	}
+	lp55xx_unregister_leds(led, chip);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(lp55xx_register_leds);