iio: ad9523: fix a missing check of return value

If ad9523_write() fails, indio_dev may get incorrect data. The fix
inserts a check for the return value of ad9523_write(), and it fails,
returns an error.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/frequency/ad9523.c

@@ -943,11 +943,14 @@ static int ad9523_setup(struct iio_dev *indio_dev)
 		}
 	}
 
-	for_each_clear_bit(i, &active_mask, AD9523_NUM_CHAN)
-		ad9523_write(indio_dev,
+	for_each_clear_bit(i, &active_mask, AD9523_NUM_CHAN) {
+		ret = ad9523_write(indio_dev,
 			     AD9523_CHANNEL_CLOCK_DIST(i),
 			     AD9523_CLK_DIST_DRIVER_MODE(TRISTATE) |
 			     AD9523_CLK_DIST_PWR_DOWN_EN);
+		if (ret < 0)
+			return ret;
+	}
 
 	ret = ad9523_write(indio_dev, AD9523_POWER_DOWN_CTRL, 0);
 	if (ret < 0)