ARM: dts: omap4-droid4: Add LCD

The LCD panel on droid 4 is a command mode LCD. The binding follows
the standard omapdrm binding and the changes needed for omapdrm command
mode panels are posted separately.

Cc: devicetree@vger.kernel.org
Cc: Marcel Partap <mpartap@gmx.net>
Cc: Michael Scott <michael.scott@linaro.org>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-By: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>