OMAPDSS: DISPC: Fix OMAP4 supported color formats

Add missing but supported color formats for GFX pipeline in dss features:
RGBX16-4444, RGBA16-4444 and XRGB16-1555.

In dispc_ovl_set_color_mode():

- Remove unsupported modes on GFX pipeline: YUV2 and UYVY. Replace these by
  missing modes supported by GFX pipelines: RGBX16-4444 and RGBA16-4444.

- Fix swapped modes on VID pipelines: RGBX16-4444 and XRGB16-4444.

Signed-off-by: Lajos Molnar <lajos@ti.com>
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>