loader.efi: Do not use as frame buffer BLT-only GOPs.
Pulled from FreeBSD:
Author: Alexander Motin <mav@FreeBSD.org>
Kernel needs physical frame buffer address and size, which Block
Transfer-only Graphics Output Protocol instances do not have.
Some recent ASUS boards like PRIME Z690M-PLUS D4 and PRIME H570-Plus
report two GOPs, out of which the second one support ConOut protocol,
that made it preferable, but is BLT-only, that made console unusable.