ARM: dts: sun8i-v3s: Add CSI0 MCLK pin definition

This adds a device-tree definition for the CSI0 MCLK pin,
which can be used for feeding MIPI CSI-2 sensors.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>

arch/arm/boot/dts/sun8i-v3s.dtsi

@@ -337,6 +337,12 @@ pio: pinctrl@1c20800 {
 			interrupt-controller;
 			#interrupt-cells = <3>;
 
+			/omit-if-no-ref/
+			csi0_mclk_pin: csi0-mclk-pin {
+				pins = "PE20";
+				function = "csi_mipi";
+			};
+
 			/omit-if-no-ref/
 			csi1_8bit_pins: csi1-8bit-pins {
 				pins = "PE0", "PE2", "PE3", "PE8", "PE9",