systemd: Delete unnecessary soft_margin

Signed-off-by: yuusuke <yusk.iida@gmail.com>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>

init/corosync.service.in

@@ -19,7 +19,7 @@ Type=forking
 #  Specify a period longer than soft_margin as RestartSec.
 #RestartSec=70
 #  rewrite according to environment.
-#ExecStartPre=/sbin/modprobe softdog soft_margin=60
+#ExecStartPre=/sbin/modprobe softdog
 
 [Install]
 WantedBy=multi-user.target