V4L/DVB (13925): gspca - main: Change the check of the USB video interface.

Some webcams have many interfaces with the same interface class, so the
previous interface check did not work.
The new code checks if the interface number is zero or the only one.
Signed-off-by: NJean-Francois Moine <moinejf@free.fr>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/gspca/gspca.c

@@ -2063,14 +2063,11 @@ int gspca_dev_probe(struct usb_interface *intf,
 		return -ENODEV;
 	}
 
-	/* check the interface class and ignore the sound interfaces */
+	/* the USB video interface must be the first one */
 	interface = &intf->cur_altsetting->desc;
-	if (interface->bInterfaceClass != USB_CLASS_VENDOR_SPEC
-	    && interface->bInterfaceClass != USB_CLASS_PER_INTERFACE) {
-		PDEBUG(D_PROBE, "Interface class %d not handled here",
-			interface->bInterfaceClass);
+	if (dev->config->desc.bNumInterfaces != 1 &&
+	    interface->bInterfaceNumber != 0)
 		return -ENODEV;
-	}
 
 	/* create the device */
 	if (dev_size < sizeof *gspca_dev)