media: media/extended-controls.rst: fix wrong enum names

MPEG4 level and profile defines were wrong. Fix this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reported-by: Nicolas Dufresne <nicolas@ndufresne.ca>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>