iio: ABI: document "sinc4+rej60" filter_type
Add a bullet point for "sinc4+rej60" filter_type that is used in the
ad7124 driver.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
authored by