ASoC: cs4270: Remove mono support

According to cs4270 datasheet, there is no reference to mono mode.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/cs4270.c

@@ -459,7 +459,7 @@ static struct snd_soc_dai_driver cs4270_dai = {
 	.name = "cs4270-hifi",
 	.playback = {
 		.stream_name = "Playback",
-		.channels_min = 1,
+		.channels_min = 2,
 		.channels_max = 2,
 		.rates = SNDRV_PCM_RATE_CONTINUOUS,
 		.rate_min = 4000,
@@ -468,7 +468,7 @@ static struct snd_soc_dai_driver cs4270_dai = {
 	},
 	.capture = {
 		.stream_name = "Capture",
-		.channels_min = 1,
+		.channels_min = 2,
 		.channels_max = 2,
 		.rates = SNDRV_PCM_RATE_CONTINUOUS,
 		.rate_min = 4000,