arm64: dts: r8a7796: Add Cortex-A57 PMU node

Enable the performance monitor unit for the Cortex-A57 cores on the
R8A7796 SoC.
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a7796.dtsi

@@ -252,6 +252,14 @@ pfc: pin-controller@e6060000 {
 			reg = <0 0xe6060000 0 0x50c>;
 		};
 
+		pmu_a57 {
+			compatible = "arm,cortex-a57-pmu";
+			interrupts = <GIC_SPI 72 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-affinity = <&a57_0>,
+					     <&a57_1>;
+		};
+
 		cpg: clock-controller@e6150000 {
 			compatible = "renesas,r8a7796-cpg-mssr";
 			reg = <0 0xe6150000 0 0x1000>;