EM/Battery: Charger helper: charger helper initial commit

EM/Battery: Charger helper: charger helper initial commit

BZ: 21548

Abstract charger operations in charger helper layer
This will expose interfaces to charger driver so that
hardware specific functions can be interfaced

Change-Id: I4a3d408f0d09d16fe9eaf2630c3f757e78165512
Signed-off-by: Amar Shankar <amarx.shankar@intel.com>
Reviewed-on: http://android.intel.com:8080/43229
Reviewed-by: Pujol, BenjaminX <benjaminx.pujol@intel.com>
Reviewed-by: Tc, Jenny <jenny.tc@intel.com>
Tested-by: P, Eshwar N <eshwar.n.p@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>