Simplify some code with Boost.Operators

Change-Id: Ic873bcbaf6be00d5c35601cfc8090df534d815ee
diff --git a/core/network.hpp b/core/network.hpp
index 227ccfc..0cf12cd 100644
--- a/core/network.hpp
+++ b/core/network.hpp
@@ -27,11 +27,13 @@
 #define NFD_CORE_NETWORK_HPP
 
 #include <boost/asio/ip/address.hpp>
+#include <boost/operators.hpp>
+
 #include <string_view>
 
 namespace nfd {
 
-class Network
+class Network : private boost::equality_comparable<Network>
 {
 public:
   Network();
@@ -62,12 +64,6 @@
            lhs.m_maxAddress == rhs.m_maxAddress;
   }
 
-  friend bool
-  operator!=(const Network& lhs, const Network& rhs) noexcept
-  {
-    return !(lhs == rhs);
-  }
-
   friend std::ostream&
   operator<<(std::ostream& os, const Network& network);