staging:iio:accel:adis16204 move to chan_spec based setup.

For clean drivers its easier to convert to chan_spec based
registration than to work around the scan_el attributes
going away.

Some minor cleanups done whilst here.

Untested.

V2: used IIO_CHAN macro

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/accel/adis16204.h

@@ -82,7 +82,7 @@ struct adis16204_state {
 	struct mutex			buf_lock;
 };
 
-int adis16204_set_irq(struct device *dev, bool enable);
+int adis16204_set_irq(struct iio_dev *indio_dev, bool enable);
 
 #ifdef CONFIG_IIO_RING_BUFFER
 enum adis16204_scan {
@@ -103,8 +103,6 @@ ssize_t adis16204_read_data_from_ring(struct device *dev,
 int adis16204_configure_ring(struct iio_dev *indio_dev);
 void adis16204_unconfigure_ring(struct iio_dev *indio_dev);
 
-int adis16204_initialize_ring(struct iio_ring_buffer *ring);
-void adis16204_uninitialize_ring(struct iio_ring_buffer *ring);
 #else /* CONFIG_IIO_RING_BUFFER */
 
 static inline void adis16204_remove_trigger(struct iio_dev *indio_dev)
@@ -133,14 +131,5 @@ static inline void adis16204_unconfigure_ring(struct iio_dev *indio_dev)
 {
 }
 
-static inline int adis16204_initialize_ring(struct iio_ring_buffer *ring)
-{
-	return 0;
-}
-
-static inline void adis16204_uninitialize_ring(struct iio_ring_buffer *ring)
-{
-}
-
 #endif /* CONFIG_IIO_RING_BUFFER */
 #endif /* SPI_ADIS16204_H_ */