[coreboot] Splashscreens

[Andy Pont]

Hello,

Using the VBT route for graphics initialisation and TianoCore as the 
payload gives two options within .config for splash screen:

CONFIG_BOOTSPLASH:
This option shows a graphical bootsplash screen. The graphics are loaded 
from the CBFS file bootsplash.jpg.

CONFIG_TIANOCORE_BOOTSPLASH_IMAGE:
Select this option if you have a bootsplash image that you would like to 
be used. If this option is not selected, the default coreboot logo 
(European Brown Hare) will used.

Do I need to define both?  What are the requirements for the images in 
terms of size, colour depth, etc?

-Andy.