Qt: Fix directory set unloading when replacing the ROM

CHANGES

@@ -11,6 +11,7 @@ Bugfixes:
  - GB Video: Clear screen when LCDC is off
  - GBA Cheats: Fix key-activated CodeBreaker cheats
  - GB SIO: Don't auto-clock external shift clock
+ - Qt: Fix directory set unloading when replacing the ROM
 Misc:
  - All: Only update version info if needed
  - FFmpeg: Encoding cleanup

src/platform/qt/GameController.cpp

@@ -507,6 +507,7 @@ void GameController::replaceGame(const QString& path) {
 	}
 	m_fname = info.canonicalFilePath();
 	threadInterrupt();
+	mDirectorySetDetachBase(&m_threadContext.core->dirs);
 	mCoreLoadFile(m_threadContext.core, m_fname.toLocal8Bit().constData());
 	threadContinue();
 }