ARM: OMAP2+: N900: remove omapdss init for DT boot

Do not try to initialize display for DT boot, since omapdss
is now initialized via Device Tree. Without this patch the
display subsystem does not properly come up.

Signed-off-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>