qv4l2: Add capture toggle and close hotkeys to CaptureWin

It can be inconvenient to stop or start the stream when the capture
window obscures most or all of the application window.  Register the
current application window stream toggle QAction to the capture
window as well.  Register a more standard Control-W to close the
window.  Add both to the context menu to allow them to be visible and
discovered.

Signed-off-by: David Fries <David@Fries.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
2 files changed