ASoC: dt-bindings: Add adi,ssm3515 amp schema

Add a DT schema for the SSM3515 amp by Analog Devices. It's a simple
mono amplifier with digital input.

Signed-off-by: Martin Povišer <povik+lin@cutebit.org
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org
Link: https://lore.kernel.org/r/20230511150546.8499-2-povik+lin@cutebit.org
Signed-off-by: Mark Brown <broonie@kernel.org

Documentation/devicetree/bindings/sound/adi,ssm3515.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/adi,ssm3515.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices SSM3515 Audio Amplifier
+
+maintainers:
+  - Martin Povišer <povik+lin@cutebit.org>
+
+description: |
+  SSM3515 is a mono Class-D audio amplifier with digital input.
+
+  https://www.analog.com/media/en/technical-documentation/data-sheets/SSM3515.pdf
+
+allOf:
+  - $ref: dai-common.yaml#
+
+properties:
+  compatible:
+    enum:
+      - adi,ssm3515
+
+  reg:
+    maxItems: 1
+
+  '#sound-dai-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      codec@14 {
+        compatible = "adi,ssm3515";
+        reg = <0x14>;
+        #sound-dai-cells = <0>;
+        sound-name-prefix = "Left Tweeter";
+      };
+    };