pmu: add kernel config for MDFLD

pmu: add kernel config for MDFLD

BZ: 17326

Added config option to enable/disable PMU driver for easy debug
and -Werror to force fix warnings

Change-Id: I7fa241c670f9fc4deade451a3d92750b7fbc9105
Signed-off-by: Prabu Renganathan <prabu.renganathan@intel.com>
Reviewed-on: http://android.intel.com:8080/27242
Reviewed-by: Mansoor, Illyas <illyas.mansoor@intel.com>
Reviewed-by: Mai, Leonard <leonard.mai@intel.com>
Tested-by: Martin, LoicX <loicx.martin@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>