writeback: add bg_threshold parameter to __bdi_update_bandwidth()

No behavior change.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 04cf3b9..2807656 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -675,7 +675,7 @@
 static void wb_update_bandwidth(struct bdi_writeback *wb,
 				unsigned long start_time)
 {
-	__bdi_update_bandwidth(wb->bdi, 0, 0, 0, 0, start_time);
+	__bdi_update_bandwidth(wb->bdi, 0, 0, 0, 0, 0, start_time);
 }
 
 /*