[media] uvcvideo: Remove duplicate check for number of buffers in queue_setup

videobuf2 already ensures that the number of buffers will not exceed
VIDEO_MAX_FRAME, which is equal to our arbitraty limit of
UVC_MAX_VIDEO_BUFFERS. Remove the duplicate check.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>