[media] vb2: only check ret if we assigned it

Move the ret check to the right level under if (pb). It is not
used by the code before that point if pb is NULL.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/v4l2-core/videobuf2-core.c

@@ -984,11 +984,12 @@ static int __qbuf_userptr(struct vb2_buffer *vb, const void *pb)
 
 	memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
 	/* Copy relevant information provided by the userspace */
-	if (pb)
+	if (pb) {
 		ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
 				 vb, pb, planes);
 		if (ret)
 			return ret;
+	}
 
 	for (plane = 0; plane < vb->num_planes; ++plane) {
 		/* Skip the plane if already verified */
@@ -1101,11 +1102,12 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const void *pb)
 
 	memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
 	/* Copy relevant information provided by the userspace */
-	if (pb)
+	if (pb) {
 		ret = call_bufop(vb->vb2_queue, fill_vb2_buffer,
 				 vb, pb, planes);
 		if (ret)
 			return ret;
+	}
 
 	for (plane = 0; plane < vb->num_planes; ++plane) {
 		struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd);