arm64: dts: allwinner: a64: Add pinmux for RGB666 LCD

Allwinner A64's TCON0 can output RGB666 LCD signal.

Add its pinmux.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi

@@ -611,6 +611,16 @@ i2c1_pins: i2c1-pins {
 				function = "i2c1";
 			};
 
+			/omit-if-no-ref/
+			lcd_rgb666_pins: lcd-rgb666-pins {
+				pins = "PD0", "PD1", "PD2", "PD3", "PD4",
+				       "PD5", "PD6", "PD7", "PD8", "PD9",
+				       "PD10", "PD11", "PD12", "PD13",
+				       "PD14", "PD15", "PD16", "PD17",
+				       "PD18", "PD19", "PD20", "PD21";
+				function = "lcd0";
+			};
+
 			mmc0_pins: mmc0-pins {
 				pins = "PF0", "PF1", "PF2", "PF3",
 				       "PF4", "PF5";