mfd: wm831x: Remove erronious bits per word set

Since the conversion to the regmap API setting bits per word will lead to
data corruption since the regmap API already configures the bits per word
appropriately.
Signed-off-by: NMark Brown <broonie@linaro.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

drivers/mfd/wm831x-spi.c

@@ -34,7 +34,6 @@ static int wm831x_spi_probe(struct spi_device *spi)
 	if (wm831x == NULL)
 		return -ENOMEM;
 
-	spi->bits_per_word = 16;
 	spi->mode = SPI_MODE_0;
 
 	spi_set_drvdata(spi, wm831x);