dt-bindings: clock: qcom,sm8450-camcc: constrain required-opps

Be specific how many required-opps are allowed.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230119130028.106817-1-krzysztof.kozlowski@linaro.org
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: krzk

Documentation/devicetree/bindings/clock/qcom,sm8450-camcc.yaml

@@ -32,6 +32,7 @@ properties:
       A phandle and PM domain specifier for the MMCX power domain.
 
   required-opps:
+    maxItems: 1
     description:
       A phandle to an OPP node describing required MMCX performance point.