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/tools/nfdc/forwarder-general-module.cpp b/tools/nfdc/forwarder-general-module.cpp
index 417b346..1542b9f 100644
--- a/tools/nfdc/forwarder-general-module.cpp
+++ b/tools/nfdc/forwarder-general-module.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2018,  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,
@@ -46,7 +46,7 @@
     onFailure, options);
 }
 
-static time::system_clock::Duration
+static auto
 calculateUptime(const ForwarderStatus& status)
 {
   return status.getCurrentTimestamp() - status.getStartTimestamp();