dt-bindings: power: domain-idle-state: Allow idle-state-name

Allow specifying a name for idle states, similar to CPU idle states
in cpu/idle-states.yaml

Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Message-ID: <20241130-topic-idle_state_name-v1-1-d0ff67b0c8e9@oss.qualcomm.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/power/domain-idle-state.yaml

@@ -54,6 +54,11 @@ patternProperties:
           (i.e. idle states node with entry-method property is set to "psci")
           must specify this property.
 
+      idle-state-name:
+        $ref: /schemas/types.yaml#/definitions/string
+        description:
+          A string used as a descriptive name for the idle state.
+
     required:
       - compatible
       - entry-latency-us