ARM: dts: rockchip: add rk3288-veyron-jaq backlight and panel overrides

The panel which jaq uses requires the pwm duty cycle larger than 3%,
when the backlight status from power off to power on, otherwise the
backlight will flush, so we modify the second brightness-level to 8,
and when the backlight from power off to power on the pwm duty cycle
will larger than 3%.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Douglas Anderson <dianders@chromium.org>