dt-bindings: crypto: qcom,prng: document QCS615

Document QCS615 compatible for True Random Number Generator.

Signed-off-by: Abhinaba Rakshit <[e-mail]>
Acked-by: Rob Herring (Arm) <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

Documentation/devicetree/bindings/crypto/qcom,prng.yaml

···
               - qcom,ipq5332-trng
               - qcom,ipq5424-trng
               - qcom,ipq9574-trng
+              - qcom,qcs615-trng
               - qcom,qcs8300-trng
               - qcom,sa8255p-trng
               - qcom,sa8775p-trng