ASoC: tlv320aic23: Clear TLV320AIC23_MS_MASTER bit for slave mode

According to the datasheet:

Digital Audio Interface Format (07h) register:
BIT6:	Master/slave mode
	0: Slave
	1: Master

Current code sets TLV320AIC23_MS_MASTER bit for master mode,
but does not clear it for slave mode.
Signed-off-by: NAxel Lin <axel.lin@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/tlv320aic23.c

@@ -430,6 +430,7 @@ static int tlv320aic23_set_dai_fmt(struct snd_soc_dai *codec_dai,
 		iface_reg |= TLV320AIC23_MS_MASTER;
 		break;
 	case SND_SOC_DAIFMT_CBS_CFS:
+		iface_reg &= ~TLV320AIC23_MS_MASTER;
 		break;
 	default:
 		return -EINVAL;