cppcheck: Fix "one definition rule" is violation for Source.

This class is defined in two different locations:

    libs/libmythtv/channelsettings.cpp
    programs/mythfilldatabase/filldata.h

Eliminate the error by changing the class name in mythfilldatabase to
DataSource. Also change SourceList->DataSourceList to keep the
symmetry of naming.

https://en.cppreference.com/w/cpp/language/definition#One_Definition_Rule

mythtv/programs/mythfilldatabase/filldata.cpp

@@ -115,7 +115,7 @@ bool FillData::GrabDataFromFile(int id, const QString &filename)
     return true;
 }
 
-bool FillData::GrabData(const Source& source, int offset)
+bool FillData::GrabData(const DataSource& source, int offset)
 {
     QString xmltv_grabber = source.xmltvgrabber;
 
@@ -237,14 +237,14 @@ bool FillData::GrabData(const Source& source, int offset)
     return succeeded;
 }
 
-/** \fn FillData::Run(SourceList &sourcelist)
+/** \fn FillData::Run(DataSourceList &sourcelist)
  *  \brief Goes through the sourcelist and updates its channels with
  *         program info grabbed with the associated grabber.
  *  \return true if there were no failures
  */
-bool FillData::Run(SourceList &sourcelist)
+bool FillData::Run(DataSourceList &sourcelist)
 {
-    SourceList::iterator it;
+    DataSourceList::iterator it;
 
     QString status;
     QString querystr;

mythtv/programs/mythfilldatabase/filldata.h

@@ -22,7 +22,7 @@ bool updateLastRunStart();
 bool updateLastRunStatus(QString &status);
 bool updateNextScheduledRun();
 
-struct Source
+struct DataSource
 {
     int     id                        {0};
     QString name;
@@ -37,7 +37,7 @@ struct Source
     bool    xmltvgrabber_lineups      {false};
     QString xmltvgrabber_prefmethod;
 };
-using SourceList = std::vector<Source>;
+using DataSourceList = std::vector<DataSource>;
 
 class FillData
 {
@@ -50,8 +50,8 @@ class FillData
     void SetRefresh(int day, bool set);
 
     bool GrabDataFromFile(int id, const QString &filename);
-    bool GrabData(const Source& source, int offset);
-    bool Run(SourceList &sourcelist);
+    bool GrabData(const DataSource& source, int offset);
+    bool Run(DataSourceList &sourcelist);
 
     enum
     {

mythtv/programs/mythfilldatabase/mythfilldatabase.cpp

@@ -338,7 +338,7 @@ int main(int argc, char *argv[])
     }
     else
     {
-        SourceList sourcelist;
+        DataSourceList sourcelist;
 
         MSqlQuery sourcequery(MSqlQuery::InitCon());
         QString where;
@@ -362,7 +362,7 @@ int main(int argc, char *argv[])
              {
                   while (sourcequery.next())
                   {
-                       Source newsource;
+                       DataSource newsource;
 
                        newsource.id = sourcequery.value(0).toInt();
                        newsource.name = sourcequery.value(1).toString();