arm64: dts: s32v234: remove fallback compatible string arm,cortex-a9-gic

Remove fallback comaptible string arm,cortex-a9-gic to fix below warning:

/home/lizhi/source/linux-upstream-dts/arch/arm64/boot/dts/freescale/s32v234-evb.dtb: interrupt-controller@7d001000: compatible: 'oneOf' conditional failed, one must be fixed:
            ['arm,cortex-a15-gic', 'arm,cortex-a9-gic'] is too long
            /home/lizhi/source/linux-upstream-dts/arch/arm64/boot/dts/freescale/s32v234-evb.dtb: interrupt-controller@7d001000: compatible: 'oneOf' conditional failed, one must be fixed:
                    ['arm,cortex-a15-gic', 'arm,cortex-a9-gic'] is too long
                    'nvidia,tegra210-agic' was expected
                    'arm,cortex-a15-gic' is not one of ['nvidia,tegra186-agic', 'nvidia,tegra194-agic', 'nvidia,tegra234-agic']
            'arm,gic-400' was expected

Signed-off-by: Frank Li <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>

arch/arm64/boot/dts/freescale/s32v234.dtsi

@@ -89,7 +89,7 @@
 	};
 
 	gic: interrupt-controller@7d001000 {
-		compatible = "arm,cortex-a15-gic", "arm,cortex-a9-gic";
+		compatible = "arm,cortex-a15-gic";
 		#interrupt-cells = <3>;
 		#address-cells = <0>;
 		interrupt-controller;