ASoC: Factor out 7 bit register 9 bit data SPI write

This converts all the Wolfson drivers using this format (the only devices
that do) except WM8753 to use it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8988.c

@@ -979,30 +979,6 @@ static struct i2c_driver wm8988_i2c_driver = {
 #endif
 
 #if defined(CONFIG_SPI_MASTER)
-static int wm8988_spi_write(struct spi_device *spi, const char *data, int len)
-{
-	struct spi_transfer t;
-	struct spi_message m;
-	u8 msg[2];
-
-	if (len <= 0)
-		return 0;
-
-	msg[0] = data[0];
-	msg[1] = data[1];
-
-	spi_message_init(&m);
-	memset(&t, 0, (sizeof t));
-
-	t.tx_buf = &msg[0];
-	t.len = len;
-
-	spi_message_add_tail(&t, &m);
-	spi_sync(spi, &m);
-
-	return len;
-}
-
 static int __devinit wm8988_spi_probe(struct spi_device *spi)
 {
 	struct wm8988_priv *wm8988;
@@ -1013,7 +989,6 @@ static int __devinit wm8988_spi_probe(struct spi_device *spi)
 		return -ENOMEM;
 
 	codec = &wm8988->codec;
-	codec->hw_write = (hw_write_t)wm8988_spi_write;
 	codec->control_data = spi;
 	codec->dev = &spi->dev;