ENGR00298052-4 ARM: dts: imx6qdl-sabreauto: support Hannstar CABC

ENGR00298052-4 ARM: dts: imx6qdl-sabreauto: support Hannstar CABC

This patch adds a device tree node for the Hannstar CABC function.
The LVDS0 and LVDS1 interfaces of the i.MX6dql Sabreauto platform
shares a control pin for the CABC function, but LVDS1's control
wire is invalid for the unpopulated resistor R265 on the main board.
We currently disable the CABC feature since it makes a panel's
backlight unstable when display content varies considerably from
time to time.

Signed-off-by: Liu Ying <Ying.Liu@freescale.com>
(cherry picked from commit 6af4f4ac7c361a60fe05400497f644db3adcfc94)