mailmap: Stephen Jahl affiliation

Reviewed-by: Stephen Jahl <stephenjahl@gmail.com>
Signed-off-by: Loic Dachary <loic@dachary.org>
mailmap: George Ryall affiliation

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

and name normalization

Reviewed-by: Brian Rak <dn@devicenull.org>
Signed-off-by: Loic Dachary <loic@dachary.org>
mailmap: Sebastien Ponce name normalization

Signed-off-by: Loic Dachary <loic@dachary.org>
mailmap: João Eduardo Luís name normalization

Signed-off-by: Loic Dachary <loic@dachary.org>