[media] vivid: move video loopback control to the capture device

This has been on my TODO list for some time now: the control that enables the video
loopback was part of the controls of the video output device instead of the video
capture device. In practice this was quite annoying since you expect it at the capture
side since that's where you want to make the decision whether to use the TPG or looped
video.

This patch moves the control from the output to the capture side.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/Documentation/video4linux/vivid.txt b/Documentation/video4linux/vivid.txt
index 0c1b3a6..e35d376 100644
--- a/Documentation/video4linux/vivid.txt
+++ b/Documentation/video4linux/vivid.txt
@@ -895,7 +895,7 @@
 
 The way to enable video/VBI looping is currently fairly crude. A 'Loop Video'
 control is available in the "Vivid" control class of the video
-output and VBI output devices. When checked the video looping will be enabled.
+capture and VBI capture devices. When checked the video looping will be enabled.
 Once enabled any video S-Video or HDMI input will show a static test pattern
 until the video output has started. At that time the video output will be
 looped to the video input provided that: