ARM: dts: sun9i: Add 8 bit mmc pinmux setting for mmc2

mmc2 is available on port C. Add a pinmux setting for 8 bit wide eMMC.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun9i-a80.dtsi

@@ -478,6 +478,15 @@ mmc0_pins: mmc0 {
 				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
 			};
 
+			mmc2_8bit_pins: mmc2_8bit {
+				allwinner,pins = "PC6", "PC7", "PC8", "PC9",
+						 "PC10", "PC11", "PC12",
+						 "PC13", "PC14", "PC15";
+				allwinner,function = "mmc2";
+				allwinner,drive = <SUN4I_PINCTRL_30_MA>;
+				allwinner,pull = <SUN4I_PINCTRL_NO_PULL>;
+			};
+
 			uart0_pins_a: uart0@0 {
 				allwinner,pins = "PH12", "PH13";
 				allwinner,function = "uart0";