media: media.h: reorder video en/decoder functions

Keep the function defines in numerical order: 0x6000 comes after
0x2000, so move it back.

Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>