ASoC: wm8940: Fix setting PLL Output clock division ratio

According to the datasheet:
The PLL Output clock division ratio is controlled by BIT[5:4] of
WM8940_GPIO register(08h).
Current code read/write the WM8940_ADDCNTRL(07h) register which is wrong.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8940.c

@@ -627,8 +627,8 @@ static int wm8940_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
 		ret = snd_soc_write(codec, WM8940_CLOCK, reg | (div << 5));
 		break;
 	case WM8940_OPCLKDIV:
-		reg = snd_soc_read(codec, WM8940_ADDCNTRL) & 0xFFCF;
-		ret = snd_soc_write(codec, WM8940_ADDCNTRL, reg | (div << 4));
+		reg = snd_soc_read(codec, WM8940_GPIO) & 0xFFCF;
+		ret = snd_soc_write(codec, WM8940_GPIO, reg | (div << 4));
 		break;
 	}
 	return ret;