forklift: Support FROMGIT patches

Add a couple arguments to generate-report which allow the caller to
specify a subject prefix other than UPSTREAM and to specify a remote
tree for the "cherry from commit" line. These can be used to facilitate
FROMGIT forklifts.

Change-Id: I83c9a99c7b7bb5855fc2884cf248ff0168108f17
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2989688
Reviewed-by: Drew Davenport <ddavenport@chromium.org>
Tested-by: Sean Paul <seanpaul@chromium.org>
Commit-Queue: Sean Paul <seanpaul@chromium.org>
1 file changed