sunxi: dts: enable SPI0 controller for A20 OLinuXino LIME 2

arch/arm/dts/sun7i-a20-olinuxino-lime2.dts

@@ -53,6 +53,7 @@
 
 	aliases {
 		serial0 = &uart0;
+		spi0 = &spi0;
 	};
 
 	chosen {
@@ -91,6 +92,19 @@
 	};
 };
 
+&pio {
+	spi0_pins: pinctrl {
+		pins = "PC0", "PC1", "PC2", "PC23";
+		drive-strength = <10>;
+		bias-disable;
+	};
+};
+
+&spi0 {
+	pinctrl-0 = <&spi0_pins>;
+	status = "okay";
+};
+
 &ahci {
 	target-supply = <&reg_ahci_5v>;
 	status = "okay";