dts: nordic: Remove cpu property from VPR nodes

It's a superfluous value which used to be required by tooling, but now
we can remove it.

Signed-off-by: Grzegorz Swiderski <[email protected]>

Author: 57300

dts/bindings/riscv/nordic,nrf-vpr-coprocessor.yaml

@@ -12,11 +12,6 @@ description: |
 include: base.yaml
 
 properties:
-  cpu:
-    type: int
-    description: |
-      Processor ID of the VPR core.
-
   execution-memory:
     type: phandle
     required: true

dts/common/nordic/nrf54h20.dtsi

@@ -588,7 +588,6 @@
 				compatible = "nordic,nrf-vpr-coprocessor";
 				reg = <0x908000 0x1000>;
 				status = "disabled";
-				cpu = <13>;
 				#address-cells = <1>;
 				#size-cells = <1>;
 				ranges = <0x0 0x908000 0x1000>;