dt-bindings: input: touchscreen: sitronix,st1232: Add wakeup-source

Document the 'wakeup-source' property for Sitronix ST1232 touchscreen
controllers to allow the device to wake the system from suspend.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260309000319.74880-2-phucduc.bui@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/sitronix,st1232.yaml

@@ -32,6 +32,9 @@ properties:
     description: A phandle to the reset GPIO
     maxItems: 1
 
+  wakeup-source:
+    type: boolean
+
 required:
   - compatible
   - reg
@@ -51,6 +54,7 @@ examples:
                     reg = <0x55>;
                     interrupts = <2 0>;
                     gpios = <&gpio1 166 0>;
+                    wakeup-source;
 
                     touch-overlay {
                             segment-0 {