tools: extend nfdc help to cover more cases

Change-Id: I0cd182c8635b15c8ffb750c913e14fa99e595d45
Refs: #4503
diff --git a/tools/nfdc/available-commands.cpp b/tools/nfdc/available-commands.cpp
index 272c13d..fca0745 100644
--- a/tools/nfdc/available-commands.cpp
+++ b/tools/nfdc/available-commands.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2017,  Regents of the University of California,
+ * Copyright (c) 2014-2018,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -25,7 +25,6 @@
 
 #include "available-commands.hpp"
 #include "face-module.hpp"
-#include "help.hpp"
 #include "rib-module.hpp"
 #include "status.hpp"
 #include "strategy-choice-module.hpp"
@@ -37,7 +36,6 @@
 void
 registerCommands(CommandParser& parser)
 {
-  registerHelpCommand(parser);
   registerStatusCommands(parser);
   FaceModule::registerCommands(parser);
   RibModule::registerCommands(parser);