iio: adc: ti-ads131e08: add missing fwnode_handle_put() in ads131e08_alloc_channels()

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: d935eddd ("iio: adc: Add driver for Texas Instruments ADS131E0x ADC family")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Link: https://lore.kernel.org/r/20220517033020.2033324-1-zhangjialin11@huawei.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/ti-ads131e08.c

@@ -739,7 +739,7 @@ static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
 	device_for_each_child_node(dev, node) {
 		ret = fwnode_property_read_u32(node, "reg", &channel);
 		if (ret)
-			return ret;
+			goto err_child_out;
 
 		ret = fwnode_property_read_u32(node, "ti,gain", &tmp);
 		if (ret) {
@@ -747,7 +747,7 @@ static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
 		} else {
 			ret = ads131e08_pga_gain_to_field_value(st, tmp);
 			if (ret < 0)
-				return ret;
+				goto err_child_out;
 
 			channel_config[i].pga_gain = tmp;
 		}
@@ -758,7 +758,7 @@ static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
 		} else {
 			ret = ads131e08_validate_channel_mux(st, tmp);
 			if (ret)
-				return ret;
+				goto err_child_out;
 
 			channel_config[i].mux = tmp;
 		}
@@ -784,6 +784,10 @@ static int ads131e08_alloc_channels(struct iio_dev *indio_dev)
 	st->channel_config = channel_config;
 
 	return 0;
+
+err_child_out:
+	fwnode_handle_put(node);
+	return ret;
 }
 
 static void ads131e08_regulator_disable(void *data)