ARM: dts: exynos5250: Add Spring device tree

Adds initial support for the HP Chromebook 11.

Cc: Vincent Palatin <vpalatin@chromium.org>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Stephan van Schaik <stephan@synkhronix.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
ARM: dts: exynos5250: Add backlight to Spring

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
ARM: dts: exynos5250: Add trackpad to Spring

Signed-off-by: Andreas Färber <andreas.faerber@web.de>