arm64: dts: amd: use "okay" for status

"okay" over "ok" is preferred for status property.

Link: https://lore.kernel.org/r/20230127101829.93761-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>