syntax fix

Author: Andreas Pettersson

app/tool/tasks/inv_vref_scan.cxx

@@ -7,6 +7,8 @@
 
 ENABLE_LOGGING();
 
+DataFitter::DataFitter() {};
+
 template <typename T>
 double median(std::vector<T>& val) {
     size_t n = val.size();

app/tool/tasks/inv_vref_scan.h

@@ -8,12 +8,10 @@
  * Perform INV_VREF scan for each link
  * used to trim adc pedestals between two links
  */
-void inv_vref_scan(Target* tgt);
-
 class DataFitter
 {
   public:
-    void DataFitter();
+    DataFitter();
 
     // Member functions
 
@@ -32,3 +30,5 @@ class DataFitter
     std::vector<Point> nonlinear_;
 
 };
+
+void inv_vref_scan(Target* tgt);