ARM: gr8: evb: Add i2s codec

The GR8-EVB comes with a wm8978 codec connected to the i2s bus.

Add a card in order to have it working
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun5i-gr8-evb.dts

@@ -76,7 +76,22 @@ backlight: backlight {
 		default-brightness-level = <8>;
 	};
 
-	spdif {
+	sound-analog {
+		compatible = "simple-audio-card";
+		simple-audio-card,name = "gr8-evb-wm8978";
+		simple-audio-card,format = "i2s";
+		simple-audio-card,mclk-fs = <512>;
+
+		simple-audio-card,cpu {
+			sound-dai = <&i2s0>;
+		};
+
+		simple-audio-card,codec {
+			sound-dai = <&wm8978>;
+		};
+	};
+
+	sound-spdif {
 		compatible = "simple-audio-card";
 		simple-audio-card,name = "On-board SPDIF";