dt-bindings: iio: adc: ti,am3359-adc: add ti,am654-adc

Document the ti,am654-adc compatible already used in DTS:

  arch/arm64/boot/dts/ti/k3-am642-evm.dtb: adc: compatible:0: 'ti,am654-adc' is not one of ['ti,am3359-adc', 'ti,am4372-adc']

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220727155203.320929-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/ti,am3359-adc.yaml

@@ -11,9 +11,14 @@ maintainers:
 
 properties:
   compatible:
-    enum:
-      - ti,am3359-adc
-      - ti,am4372-adc
+    oneOf:
+      - enum:
+          - ti,am3359-adc
+          - ti,am4372-adc
+      - items:
+          - enum:
+              - ti,am654-adc
+          - const: ti,am3359-adc
 
   '#io-channel-cells':
     const: 1