dt-bindings: soc: qcom: stats: Add QMP handle

The stats can be expanded by poking the Always-On Subsystem through QMP.
Allow passing a QMP handle for configurations that support it.

Signed-off-by: Konrad Dybcio <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bjorn Andersson <[e-mail]>

Documentation/devicetree/bindings/soc/qcom/qcom-stats.yaml

···
   reg:
     maxItems: 1
 
+  qcom,qmp:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: Reference to the AOSS side-channel message RAM
+
 required:
   - compatible
   - reg
+
+allOf:
+  - if:
+      not:
+        properties:
+          compatible:
+            const: qcom,rpmh-stats
+    then:
+      properties:
+        qcom,qmp: false
 
 additionalProperties: false