we skip downloading blob repositories, and we delete errant
blobs in lbmk. the CONFIG_USE_BLOBS option, if enabled, can
make the coreboot build system download certain binary blobs,
which we are to avoid in the canoeboot project.
in practise, canoeboot releases are already deblobbed. this change
just makes it less likely that there will be rgressions in future.
Signed-off-by: Leah Rowe <leah@libreboot.org>
9429287d6f