style: made container APIs more consistent.

Change-Id: Ib4feedfc4c9fb497dfcd67e7e6a33ee03db58d7f
refs: #4337
diff --git a/src/route/nexthop-list.hpp b/src/route/nexthop-list.hpp
index 1c35079..9ba0772 100644
--- a/src/route/nexthop-list.hpp
+++ b/src/route/nexthop-list.hpp
@@ -76,13 +76,7 @@
   removeNextHop(const NextHop& nh);
 
   size_t
-  getSize()
-  {
-    return m_nexthopList.size();
-  }
-
-  size_t
-  getSize() const
+  size() const
   {
     return m_nexthopList.size();
   }