util/release: Update build-release script

- Put parameter comments and help text in the same order as the actual
parameters.
- Don't clone a new release tree from coreboot.org if a tree already
exists.
- Change COMMIT_ID parameter from optional to required.  If it was
omitted previously, the head of the master branch would be used.

Change-Id: Ifa434a4911dec777004788e3cf4e3436875d929b
Signed-off-by: Martin Roth <martinroth@google.com>
Reviewed-on: https://review.coreboot.org/19126
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philippe Mathieu-Daudé <philippe.mathieu.daude@gmail.com>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
1 file changed