ARM: dts: imx6qdl: vicut1: The sgtl5000 uses i2s not ac97

According to Documentation/devicetree/bindings/sound/fsl,ssi.txt
'fsl,mode' should be specified for AC97 mode only.

The 'fsl,ssi' documentation doesn't say anything about specifying
'sound-dai-cells' so we'll remove that as well.
Signed-off-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-vicut1.dtsi

@@ -393,8 +393,6 @@ &pwm3 {
 };
 
 &ssi1 {
-	#sound-dai-cells = <0>;
-	fsl,mode = "ac97-slave";
 	status = "okay";
 };