media: uvcvideo: Fix smatch warning

drivers/media/usb/uvc/uvc_video.c: drivers/media/usb/uvc/uvc_video.c:1893 uvc_video_start_transfer() warn: argument 2 to %u specifier is cast from pointer

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/usb/uvc/uvcvideo.h

@@ -620,8 +620,10 @@ struct uvc_streaming {
 	     (uvc_urb) < &(uvc_streaming)->uvc_urb[UVC_URBS]; \
 	     ++(uvc_urb))
 
-#define uvc_urb_index(uvc_urb) \
-	(unsigned int)((uvc_urb) - (&(uvc_urb)->stream->uvc_urb[0]))
+static inline u32 uvc_urb_index(const struct uvc_urb *uvc_urb)
+{
+	return uvc_urb - &uvc_urb->stream->uvc_urb[0];
+}
 
 struct uvc_device_info {
 	u32	quirks;