staging:iio:ad7606: Remove unused int_vref_mv field

Remove the int_vref_mv field from the ad7606_chip_info struct since the
field is never used by the driver. The value is also the same for all
derivatives of this chip, so if it will ever be used in the driver a
constant value will work just fine.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/staging/iio/adc/ad7606.h

@@ -43,14 +43,12 @@ struct ad7606_platform_data {
 /**
  * struct ad7606_chip_info - chip specific information
  * @name:		identification string for chip
- * @int_vref_mv:	the internal reference voltage
  * @channels:		channel specification
  * @num_channels:	number of channels
  */
 
 struct ad7606_chip_info {
 	const char			*name;
-	u16				int_vref_mv;
 	const struct iio_chan_spec	*channels;
 	unsigned int			num_channels;
 };

drivers/staging/iio/adc/ad7606_core.c

@@ -261,19 +261,16 @@ static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {
 	 */
 	[ID_AD7606_8] = {
 		.name = "ad7606",
-		.int_vref_mv = 2500,
 		.channels = ad7606_channels,
 		.num_channels = 9,
 	},
 	[ID_AD7606_6] = {
 		.name = "ad7606-6",
-		.int_vref_mv = 2500,
 		.channels = ad7606_channels,
 		.num_channels = 7,
 	},
 	[ID_AD7606_4] = {
 		.name = "ad7606-4",
-		.int_vref_mv = 2500,
 		.channels = ad7606_channels,
 		.num_channels = 5,
 	},