cros_utils: clean up unused file/code

As an effort to fix up naming in crbug.com/1099035, we can just
remove the unused code and variable in these two files.

BUG=chromium:1099035
TEST=buildbot_utils_unittest.py pass after the removal.

Change-Id: Id4c12aeab9bf44b67e58b11c4297ceafe441421d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2270723
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>
Commit-Queue: Tiancong Wang <tcwang@google.com>
Tested-by: Tiancong Wang <tcwang@google.com>
2 files changed