omapfb's private copy of omapdss is now ready to be used.

This patch makes omapfb use its private omapdss and display drivers, and
also makes omap_vout (which uses omapfb) to depend on omapfb.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>