ARM: dts: uniphier: add audio out pin-mux node

The UniPhier AIO2013 audio system needs I2S and clock signal pins
to connect external codec chip.
Signed-off-by: NKatsuhiro Suzuki <suzuki.katsuhiro@socionext.com>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

arch/arm/boot/dts/uniphier-pinctrl.dtsi

@@ -8,6 +8,11 @@
  */
 
 &pinctrl {
+	pinctrl_aout: aout_grp {
+		groups = "aout";
+		function = "aout";
+	};
+
 	pinctrl_emmc: emmc_grp {
 		groups = "emmc", "emmc_dat8";
 		function = "emmc";