DEVELOPERS: add entries for recently added/modified code

This commit updates the DEVELOPERS files with packages or defconfigs
recently added, plus additional entries for developers who have modified
packages they are usually taking care of.

Cc: Christian Stewart <christian@paral.in>
Cc: Cyril Bur <cyrilbur@gmail.com>
Cc: Danomi Manchego <danomimanchego123@gmail.com>
Cc: Eric Le Bihan <eric.le.bihan.dev@free.fr>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Cc: Gustavo Zacarias <gustavo@zacarias.com.ar>
Cc: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Manuel Vögele <develop@manuel-voegele.de>
Cc: Mathieu Audat <mathieu.audat@savoirfairelinux.com>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Peter Seiderer <ps.report@gmx.net>
Cc: Piotr Nakraszewicz <piotr.nakraszewicz@imgtec.com>
Cc: Romain Perier <romain.perier@free-electrons.com>
Cc: Theo Debrouwere <t.debrouwere@televic.com>
Cc: Yann E. MORIN <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: Peter Seiderer <ps.report@gmx.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>