Check /var/run/pluto/ipsec.info for existence before sourcing it.

Thanks to Gordon Messmer
https://bugzilla.redhat.com/show_bug.cgi?id=887674#c45

src/nm-l2tp-service.c

@@ -899,13 +899,13 @@ nm_l2tp_start_ipsec(NML2tpPlugin *plugin,
 	}
 	sprintf(session_name, "nm-ipsec-l2tpd-%d", getpid());
 
-	sys += system(". /var/run/pluto/ipsec.info;"
+	sys += system("test -e /var/run/pluto/ipsec.info && . /var/run/pluto/ipsec.info;"
 	"PATH=/usr/local/sbin:/usr/sbin:/sbin; export PATH;"
 	"[ \"x$defaultrouteaddr\" = \"x\" ] && ipsec setup restart");
 
 	sys += system("PATH=/usr/local/sbin:/usr/sbin:/sbin ipsec whack"
 			" --listen");
-	sprintf(cmd1,". /var/run/pluto/ipsec.info;"
+	sprintf(cmd1,"test -e /var/run/pluto/ipsec.info && . /var/run/pluto/ipsec.info;"
 	"PATH=/usr/local/sbin:/usr/sbin:/sbin ipsec addconn "
 		" ${defaultrouteaddr:+--defaultroute} $defaultrouteaddr"
 		" ${defaultroutenexthop:+--defaultroutenexthop} $defaultroutenexthop"