mailmap: Guang Yang name normalization

Signed-off-by: Loic Dachary <loic@dachary.org>
mailmap: Warren Usui name normalization

Signed-off-by: Loic Dachary <loic@dachary.org>
mailmap: Florent Bautista affiliation

and name normalization

Signed-off-by: Loic Dachary <loic@dachary.org>
Merge pull request #1759 from dachary/wip-mailmap

DNM: mailmap updates

Reviewed-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>