this means the unified /tmp handling is now provided for
in both the former "fetch" and "fetch_trees" script, which
are now (respectively):
./update project repo
./update project trees
if the fetch scripts weren't cleaning /tmp before, they
now are, because lbmk handles it
Signed-off-by: Leah Rowe <leah@libreboot.org>
b9662fbe36