nb/intel/gm45: Don't allow too low values for gfx_uma_size

Too low gfx_uma_size can result in problems if the framebuffer
does not fit.

This partially reverts: 7afcfe0 "gm45: enable setting all vram sizes
from cmos"

Change-Id: I485d24198cb784db5d2cfce0a8646e861a4a1695
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/20194
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

0 files changed, 0 insertions, 0 deletions