arm64: dts: rockchip: add #sound-dai-cells to HDMI of rk3328

This patch adds #sound-dai-cells to use HDMI node as audio
codec from device tree of rk3328 boards.
Signed-off-by: Katsuhiro Suzuki <katsuhiro@katsuster.net>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3328.dtsi

@@ -667,6 +667,7 @@ hdmi: hdmi@ff3c0000 {
 		pinctrl-names = "default";
 		pinctrl-0 = <&hdmi_cec &hdmii2c_xfer &hdmi_hpd>;
 		rockchip,grf = <&grf>;
+		#sound-dai-cells = <0>;
 		status = "disabled";
 
 		ports {