usbvision: fix crash on detecting device with invalid configuration

commit fa52bd506f274b7619955917abfde355e3d19ffe upstream.

The usbvision driver crashes when a specially crafted usb device with invalid
number of interfaces or endpoints is detected. This fix adds checks that the
device has proper configuration expected by the driver.

Reported-by: Ralf Spenneberg <ralf@spenneberg.net>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
[bwh: Backport to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>