qcom: Enable Retention sleep mode on boot

Signed-off-by: bmc08gt <bmc08gt.teamb00sted@gmail.com>
qcom-common: power: Tuning and cleanups

 * Tune the governor for better power usage and interactivity
 * Reset tuning parameters if governor changes
 * Cleanup

 * Use our macros instead of string literals

Change-Id: I56f5dcc7f15e5dfbcc38338d515fd41d04662ab1