OMAP: DSS2: OMAPFB: Fix invalid bpp for PAL and NTSC modes

omapfb_mode_to_timings() sets the bpp to 0 when bootarg omapfb.mode is set to
either "pal" or "ntsc". This patch corrects this by setting the bpp to 24, as
would be done if omapdss_default_get_recommended_bpp() would be called.
Signed-off-by: NMaurus Cuelenaere <mcuelenaere@gmail.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

drivers/video/omap2/omapfb/omapfb-main.c

@@ -2038,11 +2038,11 @@ static int omapfb_mode_to_timings(const char *mode_str,
 #ifdef CONFIG_OMAP2_DSS_VENC
 	if (strcmp(mode_str, "pal") == 0) {
 		*timings = omap_dss_pal_timings;
-		*bpp = 0;
+		*bpp = 24;
 		return 0;
 	} else if (strcmp(mode_str, "ntsc") == 0) {
 		*timings = omap_dss_ntsc_timings;
-		*bpp = 0;
+		*bpp = 24;
 		return 0;
 	}
 #endif