iio: light: rpr0521 magic number to sizeof() on value read

Changed magic number to sizeof() on value read.
Signed-off-by: Mikko Koivunen <mikko.koivunen@fi.rohmeurope.com>
Acked-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/light/rpr0521.c

@@ -356,7 +356,7 @@ static int rpr0521_read_raw(struct iio_dev *indio_dev,
 
 		ret = regmap_bulk_read(data->regmap,
 				       rpr0521_data_reg[chan->address].address,
-				       &raw_data, 2);
+				       &raw_data, sizeof(raw_data));
 		if (ret < 0) {
 			rpr0521_set_power_state(data, false, device_mask);
 			mutex_unlock(&data->lock);