fwnode_handle_put() should be used when terminating
device_for_each_child_node() iteration with break or return to prevent
stale device node references from being left behind.

Fixes: d484c21b ("iio: adc: Add driver for Renesas RZ/G2L A/D converter")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20220517033526.2035735-1-zhangjialin11@huawei.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>