iio: dac: ad5064: Fix a few kerneldoc misdemeanours

Misspelling, missing description.

Fixes the following W=1 kernel build warning(s):

 drivers/iio/dac/ad5064.c:71: warning: bad line:                         internal vref.
 drivers/iio/dac/ad5064.c:83: warning: Function parameter or member 'channels' not described in 'ad5064_chip_info'
 drivers/iio/dac/ad5064.c:125: warning: Function parameter or member 'lock' not described in 'ad5064_state'
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200716135928.1456727-20-lee.jones@linaro.orgSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/dac/ad5064.c

@@ -68,8 +68,8 @@ enum ad5064_regmap_type {
  * struct ad5064_chip_info - chip specific information
  * @shared_vref:	whether the vref supply is shared between channels
  * @internal_vref:	internal reference voltage. 0 if the chip has no
-			internal vref.
- * @channel:		channel specification
+ *			internal vref.
+ * @channels:		channel specification
  * @num_channels:	number of channels
  * @regmap_type:	register map layout variant
  */
@@ -98,6 +98,7 @@ typedef int (*ad5064_write_func)(struct ad5064_state *st, unsigned int cmd,
  * @use_internal_vref:	set to true if the internal reference voltage should be
  *			used.
  * @write:		register write callback
+ * @lock:		maintain consistency between cached and dev state
  * @data:		i2c/spi transfer buffers
  */
 
@@ -111,7 +112,6 @@ struct ad5064_state {
 	bool				use_internal_vref;
 
 	ad5064_write_func		write;
-	/* Lock used to maintain consistency between cached and dev state */
 	struct mutex lock;
 
 	/*