futility: updater: refactor: isolate tempfile functions from updater_config

The updater_utils.c should not deal with updater_config directly.
Currently everything relates to generating temporary files will need
updater_config due to updater_create_temp_file. By moving that out (let
every caller to pass &cfg->tempfiles) we can detach updater_utils.c from
updater_config.

BRANCH=none
BUG=chromium:1024401
TEST=make clean && make runtests

Change-Id: I44bc4df0152596a822b1e0672f41c16825472249
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/1928358
Tested-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Joel Kitching <kitching@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Commit-Queue: Hung-Te Lin <hungte@chromium.org>
Auto-Submit: Hung-Te Lin <hungte@chromium.org>
5 files changed