ARM: dts: omap3-gta04: Add display support

This patch add support for lcd display on gta04 board. Display control
is connected to spi (used spi bitbang driver).

Signed-off-by: Marek Belisko <marek@goldelico.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>