ASoC: rt5670: Add disabled item in dmic pin enum

Currently, we will configure dmic related pin definition if pdata.dmic_en
is true. However, there is no disable option in the enum. So, any dmic is
used, all 3 dmic related pins will be configured. It may cause unexpected
pin definition. This patch adds a disable item for each dmic enum and
take it as default. So the driver will not set the pin configuration if
we don't set dmicx_data_pin in platform data.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/rt5670.h b/sound/soc/codecs/rt5670.h
index d11b9c2..84857bd 100644
--- a/sound/soc/codecs/rt5670.h
+++ b/sound/soc/codecs/rt5670.h
@@ -1967,17 +1967,20 @@
 };
 
 enum {
+	RT5670_DMIC1_DISABLED,
 	RT5670_DMIC_DATA_GPIO6,
 	RT5670_DMIC_DATA_IN2P,
 	RT5670_DMIC_DATA_GPIO7,
 };
 
 enum {
+	RT5670_DMIC2_DISABLED,
 	RT5670_DMIC_DATA_GPIO8,
 	RT5670_DMIC_DATA_IN3N,
 };
 
 enum {
+	RT5670_DMIC3_DISABLED,
 	RT5670_DMIC_DATA_GPIO9,
 	RT5670_DMIC_DATA_GPIO10,
 	RT5670_DMIC_DATA_GPIO5,