doc_rst: rename the media Sphinx suff to Documentation/media

The name of the subsystem is "media", and not "linux_tv". Also,
as we plan to add other stuff there in the future, let's
rename also the media uAPI book to media_uapi, to make it
clearer.

No functional changes.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/v4l/dev-effect.rst

@@ -0,0 +1,22 @@
+.. -*- coding: utf-8; mode: rst -*-
+
+.. _effect:
+
+************************
+Effect Devices Interface
+************************
+
+    **Note**
+
+    This interface has been be suspended from the V4L2 API implemented
+    in Linux 2.6 until we have more experience with effect device
+    interfaces.
+
+A V4L2 video effect device can do image effects, filtering, or combine
+two or more images or image streams. For example video transitions or
+wipes. Applications send data to be processed and receive the result
+data either with :ref:`read() <func-read>` and
+:ref:`write() <func-write>` functions, or through the streaming I/O
+mechanism.
+
+[to do]