leds: tlc591xx: fix leak of device node iterator

In one of the error paths of the for_each_child_of_node loop in
tlc591xx_probe, add missing call to of_node_put.

Fixes: 1ab4531ad132 ("leds: tlc591xx: simplify driver by using the managed led API")

Signed-off-by: Tobias Jordan <[e-mail]>
Reviewed-by: Marek Behún <[e-mail]>
Reviewed-by: Tomi Valkeinen <[e-mail]>
Signed-off-by: Pavel Machek <[e-mail]>

drivers/leds/leds-tlc591xx.c

···
 		led->ldev.max_brightness = TLC591XX_MAX_BRIGHTNESS;
 		err = devm_led_classdev_register_ext(dev, &led->ldev,
 						     &init_data);
-		if (err < 0)
+		if (err < 0) {
+			of_node_put(child);
 			return dev_err_probe(dev, err,
 					     "couldn't register LED %s\n",
 					     led->ldev.name);
+		}
 	}
 	return 0;
 }