GFX-Display: Enable dynamic CABC for TMD

GFX-Display: Enable dynamic CABC for TMD

BZ: 32194

This patch makes CABC dynamic depending on brightness levels.
For higher levels, higher savings are implemented for max
savings. For brightness below 50%, CABC is turned off.

Change-Id: I40283774a9e90a2dbd3822f14d8a09fe5c8521e2
Signed-off-by: Anand Bodas <anand.v.bodas@intel.com>
Signed-off-by: Tong, Bo <box.tong@intel.com>
Reviewed-on: http://android.intel.com:8080/43708
Reviewed-by: Xu, Randy <randy.xu@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>