arm64: dts: r8a7795: Add pmu device nodes

Enabling the performance monitor unit on r8a7795.

Signed-off-by: Masaru Nagai <masaru.nagai.vx@renesas.com>
Signed-off-by: Yoshifumi Hosoya <yoshifumi.hosoya.wj@renesas.com>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/r8a7795.dtsi

@@ -230,6 +230,18 @@
 			power-domains = <&cpg>;
 		};
 
+		pmu {
+			compatible = "arm,armv8-pmuv3";
+			interrupts = <GIC_SPI 72 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 74 IRQ_TYPE_LEVEL_HIGH>,
+				     <GIC_SPI 75 IRQ_TYPE_LEVEL_HIGH>;
+			interrupt-affinity = <&a57_0>,
+					     <&a57_1>,
+					     <&a57_2>,
+					     <&a57_3>;
+		};
+
 		timer {
 			compatible = "arm,armv8-timer";
 			interrupts = <GIC_PPI 13