iio: si7020: Swap data byte order

The Silicon Labs Si7013, Si7020, and Si7021 family of I2C humidity and
temperature sensors deliver 16 bit data high byte first.

See the datasheet available at:
https://www.silabs.com/Support%20Documents%2fTechnicalDocs%2fSi7020-A20.pdf

But as documented in Documentation/i2c/smbus-protocol,
i2c_smbus_read_word_data() expects the low byte first.

Change the driver to use i2c_smbus_read_word_swapped to get correct byte
order.
Signed-off-by: NChris Lesiak <chris.lesiak@licor.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

drivers/iio/humidity/si7020.c

@@ -50,10 +50,10 @@ static int si7020_read_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		ret = i2c_smbus_read_word_data(*client,
-					       chan->type == IIO_TEMP ?
-					       SI7020CMD_TEMP_HOLD :
-					       SI7020CMD_RH_HOLD);
+		ret = i2c_smbus_read_word_swapped(*client,
+						  chan->type == IIO_TEMP ?
+						  SI7020CMD_TEMP_HOLD :
+						  SI7020CMD_RH_HOLD);
 		if (ret < 0)
 			return ret;
 		*val = ret >> 2;