Code coverage requires `lcov`, so update the docs to call it out specifically. Signed-off-by: Paul Fagerburg <pfagerburg@google.com> Change-Id: Ie2898faa5188a7174c4e56ba34f1a4f02f939b03 Reviewed-on: https://review.coreboot.org/c/coreboot/+/58633 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Martin Roth <martinroth@google.com>