arm64: dts: freescale: Add pmu support on imx8mp

Add PMU node to enable pmu support on imx8mp.
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mp.dtsi

@@ -133,6 +133,13 @@ clk_ext4: clock-ext4 {
 		clock-output-names = "clk_ext4";
 	};
 
+	pmu {
+		compatible = "arm,cortex-a53-pmu";
+		interrupts = <GIC_PPI 7
+			     (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
+		interrupt-affinity = <&A53_0>, <&A53_1>, <&A53_2>, <&A53_3>;
+	};
+
 	psci {
 		compatible = "arm,psci-1.0";
 		method = "smc";