Add the cmake option for flatpak.

src/main/main.cpp

@@ -602,14 +602,12 @@ int main(int argc, char** argv) {
     SDL_setenv("SDL_AUDIODRIVER", "wasapi", true);
 #endif
 
-#if 0
 #if defined(__linux__) && defined(RECOMP_FLATPAK)
     // When using Flatpak, applications tend to launch from the home directory by default.
     // Mods might use the current working directory to store the data, so we switch it to a directory
     // with persistent data storage and write permissions under Flatpak to ensure it works.
     std::error_code ec;
     std::filesystem::current_path("/var/data", ec);
-#endif
 #endif
 
     // Initialize SDL audio and set the output frequency.