Merge patch series "dt-bindings: riscv: cpus: switch to unevaluatedProperties: false"

Conor Dooley <conor@kernel.org> says:

From: Conor Dooley <conor.dooley@microchip.com>

Do the various bits needed to drop the additionalProperties: true that
we currently have in riscv/cpu.yaml, to permit actually enforcing what
people put in cpus nodes.

* b4-shazam-merge:
  dt-bindings: riscv: cpus: switch to unevaluatedProperties: false
  dt-bindings: riscv: cpus: add a ref the common cpu schema

Link: https://lore.kernel.org/r/20230615-creamer-emu-ade0fa0bdb68@spud
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>