arm64: dts: broadcom: northstar2: Drop "arm,cci-400-pmu" fallback compatible

The "arm,cci-400-pmu" compatible is not documented as a valid fallback
nor is it used, so drop it.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20260106-dt-dtbs-broadcom-fixes-v1-13-ba45874e4553@kernel.org
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

Author: robherring

arch/arm64/boot/dts/broadcom/northstar2/ns2.dtsi

@@ -505,8 +505,7 @@
 			ranges = <0 0x65590000 0x10000>;
 
 			pmu@9000 {
-				compatible = "arm,cci-400-pmu,r1",
-					     "arm,cci-400-pmu";
+				compatible = "arm,cci-400-pmu,r1";
 				reg = <0x9000 0x4000>;
 				interrupts = <GIC_SPI 344 IRQ_TYPE_LEVEL_HIGH>,
 					     <GIC_SPI 345 IRQ_TYPE_LEVEL_HIGH>,