leds: max77693: Add missing of_node_put

Each break out of the for_each_available_child_of_node loop requires
of_node_put().

This patch adds missing of_node_put() when loop breaks on conflicting
values of led-sources DT property.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>

drivers/leds/leds-max77693.c

@@ -648,6 +648,7 @@ static int max77693_led_parse_dt(struct max77693_led_device *led,
 		if (sub_nodes[fled_id]) {
 			dev_err(dev,
 				"Conflicting \"led-sources\" DT properties\n");
+			of_node_put(child_node);
 			return -EINVAL;
 		}