Fix PPPoE test case issues

Change-Id: I8b57250d5578ec7979c99da15d0ed7d0b70a8872
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>
diff --git a/test/vpp_pppoe_interface.py b/test/vpp_pppoe_interface.py
index 9a8b869..fbb78bc 100644
--- a/test/vpp_pppoe_interface.py
+++ b/test/vpp_pppoe_interface.py
@@ -1,7 +1,7 @@
 
 from vpp_interface import VppInterface
 import socket
-from util import ppp, ppc, mactobinary
+from util import mactobinary
 
 
 class VppPppoeInterface(VppInterface):
@@ -12,8 +12,6 @@
     def __init__(self, test, client_ip, client_mac,
                  session_id, decap_vrf_id=0):
         """ Create VPP PPPoE4 interface """
-        self._sw_if_index = 0
-        super(VppPppoeInterface, self).__init__(test)
         self._test = test
         self.client_ip = client_ip
         self.client_mac = client_mac
@@ -28,6 +26,7 @@
                 session_id=self.session_id,
                 decap_vrf_id=self.decap_vrf_id)
         self._sw_if_index = r.sw_if_index
+        super(VppPppoeInterface, self).__init__(self._test)
         self.generate_remote_hosts()
 
     def remove_vpp_config(self):
@@ -39,41 +38,3 @@
                 session_id=self.session_id,
                 decap_vrf_id=self.decap_vrf_id,
                 is_add=0)
-
-
-class VppPppoe6Interface(VppInterface):
-    """
-    VPP Pppoe IPv6 interface
-    """
-
-    def __init__(self, test, src_ip, dst_ip, outer_fib_id=0, is_teb=0):
-        """ Create VPP PPPoE6 interface """
-        self._sw_if_index = 0
-        super(VppPppoe6Interface, self).__init__(test)
-        self._test = test
-        self.client_ip = client_ip
-        self.client_mac = client_mac
-        self.session_id = session_id
-        self.decap_vrf_id = decap_vrf_id
-
-    def add_vpp_config(self):
-        cip = socket.inet_pton(socket.AF_INET6, self.client_ip)
-        cmac = mactobinary(self.client_mac)
-        r = self.test.vapi.pppoe_add_del_session(
-                cip, cmac,
-                session_id=self.session_id,
-                decap_vrf_id=self.decap_vrf_id,
-                is_ip6=1)
-        self._sw_if_index = r.sw_if_index
-        self.generate_remote_hosts()
-
-    def remove_vpp_config(self):
-        cip = socket.inet_pton(socket.AF_INET6, self.client_ip)
-        cmac = mactobinary(self.client_mac)
-        self.unconfig()
-        r = self.test.vapi.pppoe_add_del_session(
-                cip, cmac,
-                session_id=self.session_id,
-                decap_vrf_id=self.decap_vrf_id,
-                is_add=0,
-                is_ip6=1)