init script: Add usergroup write permission to idle_time node.

Set usergroup write permission of idle_time node to enable idle
timeout feature.

Change-Id: If6b0a94e93b5117c4004726d62a346403f7a8ed3
CRs-Fixed: 610823
common-qcom: Add PowerHAL

 * New PowerHAL for QCOM devices based on upstream.
 * Requires libqc-opt and mpdecision
 * Includes support for new audio hints
 * Includes hook for external set_interactive bits

Change-Id: Ib5c956fedd1a4aee591b409b1524e95624324480
common-qcom: Make QC PowerHAL opt-in

 * Set TARGET_POWERHAL_VARIANT=qcom to use this version.

Change-Id: Iedf6ab57611e90b75304a515f93678a9b85e32e1
common-qcom: enable custom module name extension

Change-Id: I34d141ec19c3f01e7404067db4cbd493b5865d3a
dtbtool: add new --dt_tag switch

* Add new switch named --dt_tag (or -d)
* Allows a custom QCDT_DT_TAG
* If --dt_tag/-d is not used, it defaults to "qcom,msm-id =<" as it is today.

This should allow more flexibility with devices requiring various DT_TAGs going forward.

Change-Id: I6f6a9a55b3b94ce6103a4890b28792380fe1e274