[media] cx18: Move spinlock and vb_type initialisation into stream_init

The initialisation of vb_type in serialized_open was preventing
REQBUFS from working reliably. Remove it, and move the spinlock into
stream_init for good measure - it's only used when we have a stream
that supports videobuf anyway.

Signed-off-by: Simon Farnsworth <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/cx18/cx18-fileops.c

···
 	item->cx = cx;
 	item->type = s->type;
 
-	spin_lock_init(&s->vbuf_q_lock);
-	s->vb_type = 0;
-
 	item->open_id = cx->open_id++;
 	filp->private_data = &item->fh;
 

drivers/media/video/cx18/cx18-streams.c

···
 	init_timer(&s->vb_timeout);
 	spin_lock_init(&s->vb_lock);
 	if (type == CX18_ENC_STREAM_TYPE_YUV) {
+		spin_lock_init(&s->vbuf_q_lock);
+
 		s->vb_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 		videobuf_queue_vmalloc_init(&s->vbuf_q, &cx18_videobuf_qops,
 			&cx->pci_dev->dev, &s->vbuf_q_lock,