MAINTAINERS: Update Maintainers and Reviewers of DRM Bridge Drivers

Add myself as co-maintainer of DRM Bridge Drivers then add Jonas Karlman
and Jernej Škrabec as Reviewers of DRM Bridge Drivers.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Jernej Škrabec <jernej.skrabec@siol.net>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Jonas Karlman <jonas@kwiboo.se>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190624090851.17859-1-narmstrong@baylibre.com