arm64: dts: imx8mp-evk: Add HDMI audio sound card support

AUD2HTX works as the cpu dai in HDMI audio sound card.
This sound card only support playback/output.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mp-evk.dts

@@ -145,6 +145,13 @@ simple-audio-card,codec {
 
 	};
 
+	sound-hdmi {
+		compatible = "fsl,imx-audio-hdmi";
+		model = "audio-hdmi";
+		audio-cpu = <&aud2htx>;
+		hdmi-out;
+	};
+
 	reserved-memory {
 		#address-cells = <2>;
 		#size-cells = <2>;
@@ -198,6 +205,10 @@ &A53_3 {
 	cpu-supply = <&reg_arm>;
 };
 
+&aud2htx {
+	status = "okay";
+};
+
 &eqos {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_eqos>;