PM: hibernate: flush swap writer after marking

Flush the swap writer after, not before, marking the files, to ensure the
signature is properly written.

Fixes: 6f612af5 ("PM / Hibernate: Group swap ops")
Signed-off-by: Laurent Badel <laurentbadel@eaton.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel/power/swap.c

@@ -497,10 +497,10 @@ static int swap_writer_finish(struct swap_map_handle *handle,
 		unsigned int flags, int error)
 {
 	if (!error) {
-		flush_swap_writer(handle);
 		pr_info("S");
 		error = mark_swapfiles(handle, flags);
 		pr_cont("|\n");
+		flush_swap_writer(handle);
 	}
 
 	if (error)