dt-bindings: iio: adc: samsung,exynos: Drop touchscreen support

With last user of touchscreen via ADC (S3C24xx SoC) gone, drop the
unused has-touchscreen property and optional touchscreen interrupt for
samsung,s3c6410-adc.  The samsung,s5pv210-adc is the only platform
having two interrupts, so add a constrain for that.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250830-s3c-cleanup-adc-v2-5-4f8299343d32@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/samsung,exynos-adc.yaml

@@ -42,8 +42,6 @@ properties:
     maxItems: 2
 
   interrupts:
-    description:
-      ADC interrupt followed by optional touchscreen interrupt.
     minItems: 1
     maxItems: 2
 
@@ -58,11 +56,6 @@ properties:
       Phandle to the PMU system controller node (to access the ADC_PHY
       register on Exynos3250/4x12/5250/5420/5800).
 
-  has-touchscreen:
-    description:
-      If present, indicates that a touchscreen is connected and usable.
-    type: boolean
-
 required:
   - compatible
   - reg
@@ -114,13 +107,20 @@ allOf:
             - const: adc
 
   - if:
-      required:
-        - has-touchscreen
+      properties:
+        compatible:
+          contains:
+            const: samsung,s5pv210-adc
     then:
       properties:
         interrupts:
-          minItems: 2
-          maxItems: 2
+          items:
+            - description: main (ADC)
+            - description: pending (PENDN)
+    else:
+      properties:
+        interrupts:
+          maxItems: 1
 
 examples:
   - |