352MB VRAM causes stability issues, according to some reports

users can still set it to the higher level when building, if
they wish to

e.g.

./ifdtool --nuke me coreboot.rom

this will be used by rom release build scripts, to scrub
stuff like intel me from the rom

New x230edp_12mb target uses the
https://review.coreboot.org/c/coreboot/+/28950 patchset to add an
X230_EDP target to the default coreboot branch.
Consequently the "fhd" coreboot branch is no longer needed and has
been safely removed.

backported from newer coreboot revisions, see patch

coreboot/default/patches/0014-coreboot-default-fix-crossgcc-build.patch

osboot is now part of libreboot, and will soon shut down.
libreboot now conforms to osboot policy.

with this change, it's unlikely we'll hit errors again. previously,
some projects used were calling "python" which in context was
python3, but on some setups, the user only has python2 and python3
but no symlink for "python" (which if exists, we assumed linked to
python3)

now it's unambiguous. docs/build/ can probably be updated now, as
a result of this change, to remove the advice about that

Coreboot is enabling PECI on these CPUs which, according to Intel erratum, must
only be done after loading microcode updates, otherwise the CPUID feature set
becomes corrupted. That's my understanding, and I think this is why SpeedStep
is broken. To be specific, it could but but operating systems no longer detect
that the feature is supported. In any case, belgin on IRC found the commit in
coreboot, after a bisect, enabling PECI. This commit in Libreboot adds a patch,
reverting coreboot's PECI patch.