ASoC: dt-bindings: rt9123: Append RTQ9124 description

Document the ASoC Richtek RTQ9124 in existed RT9123 file.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://patch.msgid.link/9921d64ce4d63c24499f92ef33a4ce7cb018c60b.1749454717.git.cy_huang@richtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/richtek,rt9123.yaml

@@ -4,7 +4,7 @@
 $id: http://devicetree.org/schemas/sound/richtek,rt9123.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: Richtek RT9123 Audio Amplifier
+title: Richtek RT9123/RTQ9124 Audio Amplifier
 
 maintainers:
   - ChiYuan Huang <cy_huang@richtek.com>
@@ -15,6 +15,12 @@ description:
   support various formats, including I2S, left-justified, right-justified, and
   TDM formats.
 
+  RTQ9124 is an ultra-low output noise, digital input, mono-channel Class-D
+  power amplifier that supports a 2.1MHz switching frequency. It integrates
+  both DC and AC load diagnostics, as well as real-time load monitoring to
+  assess speaker condition. The device operates from 4.5V to 18V and delivers
+  up to 30W output power.
+
 allOf:
   - $ref: dai-common.yaml#
 
@@ -22,6 +28,7 @@ properties:
   compatible:
     enum:
       - richtek,rt9123
+      - richtek,rtq9124
 
   reg:
     maxItems: 1