ARM: dts: ls1021a: add node describing external interrupt lines

This adds a node describing the six external interrupt lines IRQ0-IRQ5
with configurable polarity.

Signed-off-by: Rasmus Villemoes <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

arch/arm/boot/dts/ls1021a.dtsi

···
 			compatible = "fsl,ls1021a-scfg", "syscon";
 			reg = <0x0 0x1570000 0x0 0x10000>;
 			big-endian;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges = <0x0 0x0 0x1570000 0x10000>;
+
+			extirq: interrupt-controller@1ac {
+				compatible = "fsl,ls1021a-extirq";
+				#interrupt-cells = <2>;
+				#address-cells = <0>;
+				interrupt-controller;
+				reg = <0x1ac 4>;
+				interrupt-map =
+					<0 0 &gic GIC_SPI 163 IRQ_TYPE_LEVEL_HIGH>,
+					<1 0 &gic GIC_SPI 164 IRQ_TYPE_LEVEL_HIGH>,
+					<2 0 &gic GIC_SPI 165 IRQ_TYPE_LEVEL_HIGH>,
+					<3 0 &gic GIC_SPI 167 IRQ_TYPE_LEVEL_HIGH>,
+					<4 0 &gic GIC_SPI 168 IRQ_TYPE_LEVEL_HIGH>,
+					<5 0 &gic GIC_SPI 169 IRQ_TYPE_LEVEL_HIGH>;
+				interrupt-map-mask = <0xffffffff 0x0>;
+			};
 		};
 
 		crypto: crypto@1700000 {