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 <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/1589555337-5498-16-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm/boot/dts/r8a7742.dtsi

@@ -18,6 +18,7 @@ / {
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
+		enable-method = "renesas,apmu";
 
 		cpu0: cpu@0 {
 			device_type = "cpu";
@@ -305,6 +306,18 @@ cpg: clock-controller@e6150000 {
 			#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 {
 			compatible = "renesas,r8a7742-rst";
 			reg = <0 0xe6160000 0 0x0100>;