iio: potentiometer: ds1803: Change to firmware provided data

Using firmware provided data to get the device specific
structure if not available fall back to id->driver_data.
Signed-off-by: Jagath Jog J <jagathjog1996@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220223163525.13399-5-jagathjog1996@gmail.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/potentiometer/ds1803.c

@@ -15,6 +15,7 @@
 #include <linux/iio/iio.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
+#include <linux/property.h>
 
 #define DS1803_WIPER_0         0xA9
 #define DS1803_WIPER_1         0xAA
@@ -166,7 +167,9 @@ static int ds1803_probe(struct i2c_client *client, const struct i2c_device_id *i
 
 	data = iio_priv(indio_dev);
 	data->client = client;
-	data->cfg = &ds1803_cfg[id->driver_data];
+	data->cfg = device_get_match_data(dev);
+	if (!data->cfg)
+		data->cfg = &ds1803_cfg[id->driver_data];
 
 	indio_dev->info = &ds1803_info;
 	indio_dev->channels = data->cfg->channels;