V4L/DVB (11948): uvcvideo: Ignore non-UVC trailing interface descriptors.

Herton Ronaldo Krzesinski from Mandriva reported that one Bison Electronics
webcam exposes a non-UVC interface descriptor. Instead of failing completely,
ignore trailing non-UVC descriptors and move on.

Thanks to Herton for reporting the problem and submitting a patch proposal.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>