[coreboot] Request to test graphics related Kconfig changes

[Nico Huber]

Hi all,

I've done a major rewrite of graphics related Kconfig settings and would
like to see it more tested. The goals of the changes are roughly:

  * Provide choices for settings that were loose booleans before
    (e.g. the method to initialize gfx, the final framebuffer setting).

  * Avoid buildtime and runtime conflicts by only prompting for
    option combinations that are supposed to work.

I've tested so far:

  * Lenovo/X200s: NGI (text mode, high-resolution mode), no gfx init
  * Lenovo/T420:  NGI and libgfxinit (both in text mode, high-
                  resolution mode), no gfx init

Would be nice if somebody could test VBIOS setups and FSP/GOP on some
systems before we submit the patch series. Current tip of my work is
here [1]. All options are now in the "Device" menu, the "Display" menu
moved below the gfx init options.

Best regards,
Nico

[1] https://review.coreboot.org/#/c/19815/