chromacs: Use repo tool for finding manifest files.

Instead of finding and including manifest files ourselves, we now
leverage the repo tool's manifest command to handle manifest file
finding and including.

BUG=chromium:1115170
TEST=Used chromacs with parsed output from repo manifest command.

Change-Id: If1020405368b1c18ac7b5d3f3a7e5a759433ede0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2349240
Tested-by: Aaron Massey <aaronmassey@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Aaron Massey <aaronmassey@chromium.org>
2 files changed