dt-bindings: serial: samsung: Add 'power-domains' property

Some Samsung UARTs are in a power domain, so allow 'power-domains'
property.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220823145649.3118479-1-robh@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>