target-bsnes: Patch up broken recent-game entries.

In f09c45f, we fixed native file picker dialogs, so they would correctly set the
"option" field to Auto when loading games, instead of leaving it set to an empty
string which effectively forced NTSC mode. However, this wouldn't fix up the old
entries in the Recent Games menu, so we will patch them up if we encounter them.

bsnes/target-bsnes/presentation/presentation.cpp

@@ -468,6 +468,20 @@ auto Presentation::updateRecentGames() -> void {
     }
   }
 
+  //replace any empty option strings with "Auto", to work around a bug in bsnes
+  //v115 and below.
+  for(auto entry : settings[{"Game/Recent"}]) {
+    auto old_games = entry.text();
+    if(!old_games) continue;
+    vector<string> new_games;
+    for(auto& game : old_games.split("|")) {
+        auto parts = game.split(";", 1L);
+        if(parts[0] == "") parts[0] = "Auto";
+        new_games.append(parts.merge(";"));
+    }
+    entry.setValue(new_games.merge("|"));
+  }
+
   //update list
   for(auto index : range(RecentGames)) {
     MenuItem item{&loadRecentGame};