arm64: dts: amazon: alpine-v2: Add default GIC address cells

Add missing address-cells 0 to GIC interrupt node to silence W=1
warning:

  alpine-v2.dtsi:138.4-139.33: Warning (interrupt_map): /soc/pci@fbc00000:interrupt-map:
    Missing property '#address-cells' in node /soc/interrupt-controller@f0200000, using 0 as fallback

Value '0' is correct because:
1. GIC interrupt controller does not have children,
2. interrupt-map property (in PCI node) consists of five components and
   the fourth component "parent unit address", which size is defined by
   '#address-cells' of the node pointed to by the interrupt-parent
   component, is not used (=0)

Link: https://lore.kernel.org/r/20250822133423.312621-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

arch/arm64/boot/dts/amazon/alpine-v2.dtsi

@@ -123,6 +123,7 @@ gic: interrupt-controller@f0200000 {
 			      <0x0 0xf0120000 0x0 0x2000>;	/* GICH */
 			interrupts = <GIC_PPI 9 IRQ_TYPE_LEVEL_HIGH>;
 			interrupt-controller;
+			#address-cells = <0>;
 			#interrupt-cells = <3>;
 		};