Add a suspend method to the log that flushes to disk, in case the
mirror has been recovering without any io.
--- diff/drivers/md/dm-log.c	2004-01-05 15:58:39.000000000 +0000
+++ source/drivers/md/dm-log.c	2004-01-07 14:40:45.000000000 +0000
@@ -564,6 +564,7 @@
 	.name = "disk",
 	.ctr = disk_ctr,
 	.dtr = disk_dtr,
+	.suspend = disk_flush,
 	.resume = disk_resume,
 	.get_region_size = core_get_region_size,
 	.is_clean = core_is_clean,