test: add test cases for ethernet interface

Change-Id: Ibf3a2b3513c784a56540488fa7de5a638a83a833
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/ethernet_interface.cpp b/ethernet_interface.cpp
index 5429bbc..0ec3f67 100644
--- a/ethernet_interface.cpp
+++ b/ethernet_interface.cpp
@@ -35,8 +35,8 @@
                                      Manager& parent) :
                                      Ifaces(bus, objPath.c_str(), true),
                                      bus(bus),
-                                     manager(parent)
-
+                                     manager(parent),
+                                     objPath(objPath)
 {
     auto intfName = objPath.substr(objPath.rfind("/") + 1);
     interfaceName(intfName);
@@ -250,8 +250,7 @@
     std::transform(type.begin(), type.end(), type.begin(), ::tolower);
 
     std::experimental::filesystem::path objectPath;
-    objectPath /= std::string(OBJ_NETWORK);
-    objectPath /= interfaceName();
+    objectPath /= objPath;
     objectPath /= type;
     objectPath /= generateId(ipaddress, prefixLength, gateway);
     return objectPath.string();