Adapt test configurations

Adapt test configurations to the new Debian-based system.

testing/tests/ikev2/dhcp-static-client-id/posttest.dat

@@ -1,7 +1,7 @@
 moon::ipsec stop
 carol::ipsec stop
 dave::ipsec stop
-venus::/etc/init.d/dhcpd stop 2> /dev/null
+venus::/etc/init.d/isc-dhcp-server stop 2> /dev/null
 moon::/etc/init.d/iptables stop 2> /dev/null
 carol::/etc/init.d/iptables stop 2> /dev/null
 dave::/etc/init.d/iptables stop 2> /dev/null