conf-file-processor: fix empty file creation if conf file is same as dynamic

refs: #5071

Change-Id: I031381156d3c9aee21bb8ab7d018a37189e4a321
diff --git a/src/conf-file-processor.hpp b/src/conf-file-processor.hpp
index 65b9a16..e33b50b 100644
--- a/src/conf-file-processor.hpp
+++ b/src/conf-file-processor.hpp
@@ -30,6 +30,9 @@
 
 namespace nlsr {
 
+namespace bf = boost::filesystem;
+using ConfigSection = boost::property_tree::ptree;
+
 /*! \brief A class containing methods to parse an NLSR configuration file
  *
  * This class contains methods to parse an NLSR configuration file and
@@ -59,8 +62,6 @@
   processConfFile();
 
 private:
-  typedef boost::property_tree::ptree ConfigSection;
-
   /*! \brief Parse the configuration file into a tree and process the nodes.
    *
    * Reads the configuration file as a property tree, and then iterates