arm64: dts: enable idle states for Hi6220

Add cpu and cluster level's low power state for Hi6220.

Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
1 file changed