Merge branch 'poll-pwc' of /home/v4l/v4l/patchwork

Merge branch 'poll-pwc' of /home/v4l/v4l/patchwork

* 'poll-pwc' of /home/v4l/v4l/patchwork:
  gspca_pac207: Raise max exposure + various autogain setting tweaks
  pwc: read new preset values when changing awb control to a preset
  pwc: poll(): Check that the device has not beem claimed for streaming already
  pwc: rework locking
  pwc: Make auto white balance speed and delay available as v4l2 controls
  pwc: properly mark device_hint as unused in all probe error paths
  pwc: Add support for control events
  vivi: let vb2_poll handle events.
  videobuf2-core: also test for pending events.
  videobuf: only start streaming in poll() if so requested by the poll mask.
  videobuf2: only start streaming in poll() if so requested by the poll mask.
  ivtv: only start streaming in poll() if polling for input.
  poll: add poll_requested_events() function