iio: dac: ad5686: cleanup doc header of local structs

Review documentation comment header for ad5686_chip_info and ad5686_state.
Update variable names and description and remove unnecessary blank line
between comment and struct declaration.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Author: rodrigo455

drivers/iio/dac/ad5686.h

@@ -69,12 +69,11 @@ typedef int (*ad5686_read_func)(struct ad5686_state *st, u8 addr);
 
 /**
  * struct ad5686_chip_info - chip specific information
- * @int_vref_mv:	AD5620/40/60: the internal reference voltage
+ * @int_vref_mv:	the internal reference voltage
  * @num_channels:	number of channels
  * @channel:		channel specification
  * @regmap_type:	register map layout variant
  */
-
 struct ad5686_chip_info {
 	u16				int_vref_mv;
 	unsigned int			num_channels;
@@ -112,16 +111,16 @@ extern const struct ad5686_chip_info ad5679r_chip_info;
 
 /**
  * struct ad5686_state - driver instance specific data
- * @spi:		spi_device
+ * @dev:		device instance
  * @chip_info:		chip model specific constants, available modes etc
  * @vref_mv:		actual reference voltage used
  * @pwr_down_mask:	power down mask
  * @pwr_down_mode:	current power down mode
  * @use_internal_vref:	set to true if the internal reference voltage is used
- * @lock		lock to protect the data buffer during regmap ops
- * @data:		spi transfer buffers
+ * @lock:		lock to protect access to state fields, which includes
+ *			the data buffer during regmap ops
+ * @data:		transfer buffers
  */
-
 struct ad5686_state {
 	struct device			*dev;
 	const struct ad5686_chip_info	*chip_info;