Working uvc/webcam driver

[Michael Neumann]

Hi,

I made some progress with the uvc/webcam driver port from FreeBSD. It's
working great in chrome, cheese and ffmpeg. But it only works *once*.
After closing the video device I still need to kldunload/kldload the
uvc driver.

The patch is here:

	https://leaf.dragonflybsd.org/~mneumann/0001-Initial-port-of-uvc-driver-from-FreeBSD.patch

Or see my github repo:

	https://github.com/mneumann/DragonFlyBSD/tree/feature-uvc-rebased

Regards,

  Michael