dt-bindings: timer: actions,owl-timer: convert to YAML

dt-bindings: timer: actions,owl-timer: convert to YAML

Convert the Actions Semi Owl timer bindings to DT schema.

Changes during conversion:
 - Add a description
 - Add "clocks" as a required property, since the driver searches for it
 - Correct the given example according to owl-s500.dtsi

Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20241103123513.2890107-1-ivo.ivanov.ivanov1@gmail.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>