dma-buf/sync_file: fix build warning with context format type

Christian König changed fence context to a u64 type, so we need to
update all users accordingly.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1464968791-4564-1-git-send-email-gustavo@padovan.org

drivers/dma-buf/sync_file.c

@@ -82,7 +82,7 @@ struct sync_file *sync_file_create(struct fence *fence)
 
 	sync_file->num_fences = 1;
 	atomic_set(&sync_file->status, 1);
-	snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%d-%d",
+	snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%llu-%d",
 		 fence->ops->get_driver_name(fence),
 		 fence->ops->get_timeline_name(fence), fence->context,
 		 fence->seqno);