PM / sleep: Refactor filesystems sync to reduce duplication

Create a common helper to sync filesystems for system suspend and
hibernation.

Signed-off-by: Harry Pan <harry.pan@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index abef759d..cc105ec 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -14,7 +14,6 @@
 
 #include <linux/export.h>
 #include <linux/suspend.h>
-#include <linux/syscalls.h>
 #include <linux/reboot.h>
 #include <linux/string.h>
 #include <linux/device.h>
@@ -709,9 +708,7 @@ int hibernate(void)
 		goto Exit;
 	}
 
-	pr_info("Syncing filesystems ... \n");
-	ksys_sync();
-	pr_info("done.\n");
+	ksys_sync_helper();
 
 	error = freeze_processes();
 	if (error)