dt-bindings: clock: Add ARTPEC-8 clock controller

dt-bindings: clock: Add ARTPEC-8 clock controller

Add dt-schema for Axis ARTPEC-8 SoC clock controller.

The Clock Management Unit (CMU) has a top-level block CMU_CMU
which generates clocks for other blocks.

Add device-tree binding definitions for following CMU blocks:
- CMU_CMU
- CMU_BUS
- CMU_CORE
- CMU_CPUCL
- CMU_FSYS
- CMU_IMEM
- CMU_PERI

Signed-off-by: Hakyeong Kim <hgkim05@coasia.com>
Signed-off-by: SeonGu Kang <ksk4725@coasia.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Ravi Patel <ravi.patel@samsung.com>
Link: https://lore.kernel.org/r/20250825114436.46882-2-ravi.patel@samsung.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>