drivers: cpuidle: lpm-levels-of: conform to arm,idle-state definition

Start confirming to arm,idle-state compatible definition. In addition to
being compliant, this allows us to use the new API to setup the PSCI
cluster state ids for the CPU, before entering the idle state.

Let's do the following:
    - Rename enter/exit latency, residency, label properties
    - In addition to qcom,psci-cpu-mode specify
      arm,psci-suspend-param.
    - Update copyright

Change-Id: I3930fce9788e8be1e43e0e7c9ff247df2ec23f55
Signed-off-by: Lina Iyer <ilina@codeaurora.org>