dt-bindings: input: touchscreen: exc3000: add EXC81W32

Add compatible for EXC81W32 touchscreen controllers.
They use the same protocol and have the same resolution as EXC80H84.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240710-input-exc3000-exc81w32-v3-1-4272183628b4@pengutronix.deSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/eeti,exc3000.yaml

@@ -14,10 +14,14 @@ allOf:
 
 properties:
   compatible:
-    enum:
-      - eeti,exc3000
-      - eeti,exc80h60
-      - eeti,exc80h84
+    oneOf:
+      - const: eeti,exc3000
+      - const: eeti,exc80h60
+      - const: eeti,exc80h84
+      - items:
+          - enum:
+              - eeti,exc81w32
+          - const: eeti,exc80h84
   reg:
     const: 0x2a
   interrupts: