cmd: adc: add info on channel mask

Enhance adc info command to report also the channel mask.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/adc.c b/cmd/adc.c
index c8857ed..39f61c1 100644
--- a/cmd/adc.c
+++ b/cmd/adc.c
@@ -35,7 +35,7 @@
 		       char *const argv[])
 {
 	struct udevice *dev;
-	unsigned int data_mask;
+	unsigned int data_mask, ch_mask;
 	int ret, vss, vdd;
 
 	if (argc < 2)
@@ -49,6 +49,10 @@
 
 	printf("ADC Device '%s' :\n", argv[1]);
 
+	ret = adc_channel_mask(dev, &ch_mask);
+	if (!ret)
+		printf("channel mask: %x\n", ch_mask);
+
 	ret = adc_data_mask(dev, &data_mask);
 	if (!ret)
 		printf("data mask: %x\n", data_mask);