evolve: fix progress display with hg<4.7
Since d1aab9d82f5b (evolve: adapt for deprecated ui.progress(),
2019-01-14), the "item", "units" and "total" are all set to default
values. The last one is especially bad since it results in a "spinner"
instead of a progress bar.
This software was downloaded from
https://www.mercurial-scm.org/repo/evolve/
Copyright 2011 Peter Arrenbrecht <peter.arrenbrecht@gmail.com>
Logilab SA <contact@logilab.fr>
Pierre-Yves David <pierre-yves.david@ens-lyon.org>
Patrick Mezard <patrick@mezard.eu>
This software may be used and distributed according to the terms of the GNU
General Public License version 2 or any later version.
On Debian systems, the complete text of the GNU General Public License version
2 can be found in `/usr/share/common-licenses/GPL-2'.