.mailmap: Add an entry for Marc-Andre Lureau

.mailmap: Add an entry for Marc-Andre Lureau

We use .mailmap to display contributors email addresses in an
uniform format.

Add an entry for Marc-André Lureau to have his/her name and email
address displayed properly in the git history.

Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Philippe Mathieu-Daude <philmd@redhat.com>
Message-Id: <20200106115415.11624-19-philmd@redhat.com>
[lersek@redhat.com: translit subject to ASCII to suppress PatchCheck.py]