[media] media: mx1_camera: Remove driver

That driver hasn't been really maintained for a long time. It doesn't
compile in any way, it includes non-existent headers, has no users,
and marked as "BROKEN" more than year. Due to these factors, mx1_camera
is now removed from the tree.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>