Reduce usage of std::bind()

C++14 lambdas are easier to read, easier to debug,
and can usually be better optimized by the compiler.

Change-Id: I294f275904f91942a8de946fe63e77078a7608a6
diff --git a/tests/tools/mock-nfd-mgmt-fixture.hpp b/tests/tools/mock-nfd-mgmt-fixture.hpp
index 7c02720..6798dd8 100644
--- a/tests/tools/mock-nfd-mgmt-fixture.hpp
+++ b/tests/tools/mock-nfd-mgmt-fixture.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2020,  Regents of the University of California,
+ * Copyright (c) 2014-2021,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -50,7 +50,7 @@
 protected:
   MockNfdMgmtFixture()
     : face(m_io, m_keyChain,
-           {true, false, bind(&MockNfdMgmtFixture::processEventsOverride, this, _1)})
+           {true, false, std::bind(&MockNfdMgmtFixture::processEventsOverride, this, _1)})
   {
     face.onSendInterest.connect([this] (const Interest& interest) {
       if (processInterest) {