dt-bindings: power: add Amlogic A4 power domains

Add devicetree binding document and related header file for
Amlogic A4 secure power domains.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Link: https://lore.kernel.org/r/20240529-a4_secpowerdomain-v2-1-47502fc0eaf3@amlogic.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>