MAINTAINERS: Move mxsfb drm driver to drm-misc tree

Another "small driver" moving into drm-misc. Stefan has also offered to
co-maintain it.

Cc: Marek Vasut <marex@denx.de>
Cc: Stefan Agner <stefan@agner.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180919204026.3217-2-sean@poorly.run

MAINTAINERS

@@ -9891,9 +9891,12 @@ F:	drivers/media/tuners/mxl5007t.*
 
 MXSFB DRM DRIVER
 M:	Marek Vasut <marex@denx.de>
+M:	Stefan Agner <stefan@agner.ch>
+L:	dri-devel@lists.freedesktop.org
 S:	Supported
 F:	drivers/gpu/drm/mxsfb/
 F:	Documentation/devicetree/bindings/display/mxsfb.txt
+T:	git git://anongit.freedesktop.org/drm/drm-misc
 
 MYRICOM MYRI-10G 10GbE DRIVER (MYRI10GE)
 M:	Chris Lee <christopher.lee@cspi.com>