dt-bindings: power: renesas,apmu: Group tuples in cpus properties

To improve human readability and enable automatic validation, the tuples
in "cpus" properties in device nodes for Advanced Power Management Units
for AP-System Core (APMU) should be grouped using angle brackets.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/power/renesas,apmu.yaml

···
     apmu@e6152000 {
             compatible = "renesas,r8a7791-apmu", "renesas,apmu";
             reg = <0xe6152000 0x188>;
-            cpus = <&cpu0 &cpu1>;
+            cpus = <&cpu0>, <&cpu1>;
     };