power: qcom: Add the QPNP QGAUGE (QG) headers

The QG headers support for battery gauging and reporting
the battery specific parameters to userspace.
This is a snapshot of header files as of msm-4.9
'commit 8f7046d0c282 (" Merge msm: ep_pcie: Disable
clkreq interrupt and release wakelock in D3 cold")'.

Change-Id: I3288e71af24bf9c3a0d814014c4f653285622f14
Signed-off-by: Kishor Krishna Bhat <kishkris@codeaurora.org>