vlan: implement delete interface

Delete the in-memory vlan object,Also
deletes the associated device file and the
network file.

Change-Id: I613e31aaa4fa9172c6226765ac044481ffbd88ec
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/vlan_interface.cpp b/vlan_interface.cpp
index f4224d4..88e3c10 100644
--- a/vlan_interface.cpp
+++ b/vlan_interface.cpp
@@ -26,14 +26,14 @@
                              uint32_t vlanID,
                              EthernetInterface& intf,
                              Manager& parent ) :
-        VlanIntfObject(bus, objPath.c_str(), true),
+        Interfaces(bus, objPath.c_str(), true),
         EthernetInterface(bus, objPath, dhcpEnabled, parent, false),
         parentInterface(intf)
 {
     id(vlanID);
     VlanIface::interfaceName(EthernetInterface::interfaceName());
 
-    VlanIntfObject::emit_object_added();
+    Interfaces::emit_object_added();
 }
 
 void VlanInterface::writeDeviceFile()
@@ -64,5 +64,10 @@
     stream.close();
 }
 
+void VlanInterface::delete_()
+{
+    parentInterface.deleteVLANObject(EthernetInterface::interfaceName());
+}
+
 }//namespace network
 }//namespace phosphor