staging: iio: adis16350 add dummy ring functions for no ring build case

Signed-off-by: NJonathan Cameron <jic23@cam.ac.uk>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/imu/adis16350.h

@@ -165,5 +165,13 @@ adis16350_read_data_from_ring(struct device *dev,
 	return 0;
 }
 
+static inline int adis16350_configure_ring(struct iio_dev *indio_dev)
+{
+	return 0;
+}
+
+static inline void adis16350_unconfigure_ring(struct iio_dev *indio_dev)
+{
+}
 #endif /* CONFIG_IIO_RING_BUFFER */
 #endif /* SPI_ADIS16350_H_ */