staging:iio:core add missing increment of loop index in iio_map_array_unregister()

staging:iio:core add missing increment of loop index in iio_map_array_unregister()
Signed-off-by: NLothar Waßmann <LW@KARO-electronics.de>
Acked-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/iio/inkern.c

@@ -82,6 +82,7 @@ int iio_map_array_unregister(struct iio_dev *indio_dev,
 			ret = -ENODEV;
 			goto error_ret;
 		}
+		i++;
 	}
 error_ret:
 	mutex_unlock(&iio_map_list_lock);