ARM: dts: r8a7742: Add APMU nodes

Add DT nodes for the Advanced Power Management Units (APMU), and use the
enable-method to point out that the APMU should be used for SMP support.

Signed-off-by: Lad Prabhakar <[e-mail]>
Reviewed-by: Marian-Cristian Rotariu <[e-mail]>
Reviewed-by: Wolfram Sang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Geert Uytterhoeven <[e-mail]>

arch/arm/boot/dts/r8a7742.dtsi

···
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
+		enable-method = "renesas,apmu";
 
 		cpu0: cpu@0 {
 			device_type = "cpu";
···
 			#clock-cells = <2>;
 			#power-domain-cells = <0>;
 			#reset-cells = <1>;
+		};
+
+		apmu@e6151000 {
+			compatible = "renesas,r8a7742-apmu", "renesas,apmu";
+			reg = <0 0xe6151000 0 0x188>;
+			cpus = <&cpu4 &cpu5 &cpu6 &cpu7>;
+		};
+
+		apmu@e6152000 {
+			compatible = "renesas,r8a7742-apmu", "renesas,apmu";
+			reg = <0 0xe6152000 0 0x188>;
+			cpus = <&cpu0 &cpu1 &cpu2 &cpu3>;
 		};
 
 		rst: reset-controller@e6160000 {