lpm-levels: Add QCOM cpuidle governor

Currently framework uses menu as governor and the mode selection happens
again in lpm driver. Register QCOM cpuidle governor, use the mode
selected for cpu to enter and further select the mode for the cluster to
enter.

Change-Id: Ifa98c4c90859f70fb5406715b53c89276ac1a4f4
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>