ggsn_tests: Validate DNS PCO values

Change-Id: I54124cb5269c0992e6c72af1a1ecaa8e3202bf05
diff --git a/ggsn_tests/GGSN_Tests.cfg b/ggsn_tests/GGSN_Tests.cfg
index 90368b9..d8994df 100644
--- a/ggsn_tests/GGSN_Tests.cfg
+++ b/ggsn_tests/GGSN_Tests.cfg
@@ -18,6 +18,8 @@
 GGSN_Tests.m_ggsn_ip_gtpu := "127.0.0.2"
 GGSN_Tests.m_ggsn_ip4_dns1 := "192.168.100.1"
 GGSN_Tests.m_ggsn_ip4_dns2 := "8.8.8.8"
+GGSN_Tests.m_ggsn_ip6_dns1 := "2001:4860:4860::8888"
+GGSN_Tests.m_ggsn_ip6_dns2 := "2001:4860:4860::8844"
 
 [EXECUTE]
 #GGSN_Tests.TC_dummy