[SeaBIOS] Splash Screen fix (RGB bits per channel)

[Kevin O'Connor]

On Mon, Apr 09, 2012 at 10:29:03AM -0600, Steve Goodrich wrote:
> Anyway, the code as written was finding the first video mode of the correct
> width/height and using that.  Unfortunately, the mode was a 5-5-5 while the
> JPG was being decoded as 5-6-5 (bits per RGB channel).

What happened when the 5-5-5 mode was chosen?  The code should still
have worked (if not as pretty looking).

-Kevin