dt-bindings: iio: adc: qcom,spmi-vadc: simplify compatible enum

The second compatible item in oneOf is just an enum, not a list.
Signed-off-by: NKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221027143411.277980-1-krzysztof.kozlowski@linaro.orgSigned-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.yaml

@@ -22,13 +22,11 @@ properties:
       - items:
           - const: qcom,pms405-adc
           - const: qcom,spmi-adc-rev2
-
-      - items:
-          - enum:
-              - qcom,spmi-vadc
-              - qcom,spmi-adc5
-              - qcom,spmi-adc-rev2
-              - qcom,spmi-adc7
+      - enum:
+          - qcom,spmi-vadc
+          - qcom,spmi-adc5
+          - qcom,spmi-adc-rev2
+          - qcom,spmi-adc7
 
   reg:
     description: VADC base address in the SPMI PMIC register map