doc-rst: linux_tv: move MC stuff to a separate dir

When we wrote the media controller's section, we re-used the
V4L, just because we were lazy to create a brand new DocBook.

Yet, it is a little ackward to have it mixed with V4L. So,
move it to its own directory, in order to have it better
organized.

No functional changes.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/linux_tv/index.rst

@@ -71,7 +71,7 @@ etc, please mail to:
     media/v4l/v4l2
     media/dvb/dvbapi
     media/rc/remote_controllers
-    media/v4l/media-controller
+    media/mediactl/media-controller
     media/v4l/gen-errors
     media/v4l/fdl-appendix