iio: gyro: clean up indentation issue

There is a return statement that is indented incorrectly, add in
the missing tab.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/gyro/itg3200_core.c

@@ -154,7 +154,7 @@ static int itg3200_write_raw(struct iio_dev *indio_dev,
 					  t);
 
 		mutex_unlock(&indio_dev->mlock);
-	return ret;
+		return ret;
 
 	default:
 		return -EINVAL;