dm log: split suspend

There are now two phases to a suspend in device-mapper -
presuspend and postsuspend.  This patch removes the
single 'suspend' in the logging API and replaces it with
'presuspend' and 'postsuspend' functions to align it
better with core device-mapper.

A subsequent patch will make use of 'presuspend'.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index a66428d8..072ee43 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -696,7 +696,7 @@
 	.module = THIS_MODULE,
 	.ctr = disk_ctr,
 	.dtr = disk_dtr,
-	.suspend = disk_flush,
+	.postsuspend = disk_flush,
 	.resume = disk_resume,
 	.get_region_size = core_get_region_size,
 	.is_clean = core_is_clean,