dt-bindings: remoteproc: qcom: Add QMP property

Add Qualcomm Mailbox Protocol (QMP) property to replace the power domain
exposed by the AOSS QMP node.
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/1631800770-371-4-git-send-email-sibis@codeaurora.org

Documentation/devicetree/bindings/remoteproc/qcom,q6v5.txt

@@ -174,7 +174,12 @@ For the compatible string below the following supplies are required:
 		    must be "cx", "mx"
 	qcom,sc7180-mss-pil:
 	qcom,sdm845-mss-pil:
-		    must be "cx", "mx", "mss", "load_state"
+		    must be "cx", "mx", "mss"
+
+- qcom,qmp:
+	Usage: optional
+	Value type: <phandle>
+	Definition: reference to the AOSS side-channel message RAM.
 
 - qcom,smem-states:
 	Usage: required