firmware: Add LCOV tarball information

Add info about an LCOV tarball for EC code coverage.

BUG=b:156895937
TEST=generate

Change-Id: I39e21ebf696c8d9b9434b680171f38d38f3ee830
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2762018
Commit-Queue: Paul Fagerburg <pfagerburg@chromium.org>
Commit-Queue: LaMont Jones <lamontjones@chromium.org>
Auto-Submit: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: LaMont Jones <lamontjones@chromium.org>
2 files changed