arm64: dts: qcom: qcs404: Add PSCI cpuidle low power states

Add device bindings for cpuidle states for cpu devices.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
[amit: rename the idle-states to more generic names and fixups]
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Signed-off-by: Andy Gross <agross@kernel.org>