mailmap: update email addresses for Luc Michel

Map my old and now invalid work email addresses to my personal one.

Signed-off-by: Luc Michel <luc@lmichel.fr>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230929140326.2056658-2-luc@lmichel.fr>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>