V4L/DVB: uvc: Enable USB autosuspend by default on uvcvideo

We've been doing this for a while in Fedora without any complaints.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>