core+daemon: declare all equality operators as hidden friends

Change-Id: Id832ee1fb16fb6742879c8b87f56002f94745103
diff --git a/daemon/face/network-predicate.cpp b/daemon/face/network-predicate.cpp
index 340ef82..798ceeb 100644
--- a/daemon/face/network-predicate.cpp
+++ b/daemon/face/network-predicate.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2022,  Regents of the University of California,
+ * Copyright (c) 2014-2023,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -163,13 +163,6 @@
   }
 }
 
-bool
-NetworkPredicateBase::operator==(const NetworkPredicateBase& other) const
-{
-  return this->m_whitelist == other.m_whitelist &&
-         this->m_blacklist == other.m_blacklist;
-}
-
 static bool
 doesMatchPattern(const std::string& ifname, const std::string& pattern)
 {