ARM: dts: imx7d-sdb: Add HDMI audio sound card

Add HDMI audio sound card, the interface is sii902x.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx7d-sdb.dts

@@ -164,6 +164,13 @@ sound {
 			"LINPUT1", "AMIC",
 			"AMIC", "MICB";
 	};
+
+	sound-hdmi {
+		compatible = "fsl,imx-audio-sii902x";
+		model = "sii902x-audio";
+		audio-cpu = <&sai3>;
+		hdmi-out;
+	};
 };
 
 &adc1 {