dt-bindings: soc: qcom: smd-rpm: Add IPQ6018 compatible

This patch adds the dt-binding for the rpm on the Qualcomm IPQ6018
platform.
Signed-off-by: Kathiravan T <kathirav@codeaurora.org>
Link: https://lore.kernel.org/r/1595225543-12127-2-git-send-email-kathirav@codeaurora.orgSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Documentation/devicetree/bindings/soc/qcom/qcom,smd-rpm.txt

@@ -20,6 +20,7 @@ resources.
 	Value type: <string>
 	Definition: must be one of:
 		    "qcom,rpm-apq8084"
+		    "qcom,rpm-ipq6018"
 		    "qcom,rpm-msm8916"
 		    "qcom,rpm-msm8936"
 		    "qcom,rpm-msm8974"