[*] basic in-house cpp linting (#4039)

- add `#pragma once` to remainder files
- "correcter" defines (ANDROID), see https://groups.google.com/g/android-ndk/c/cf9_f1SLXls
- extra miscelly fixups

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4039
Reviewed-by: MaranBr <maranbr@eden-emu.dev>
Reviewed-by: crueter <crueter@eden-emu.dev>

src/yuzu/migration_dialog.h

@@ -1,8 +1,7 @@
 // SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
-#ifndef MIGRATION_DIALOG_H
-#define MIGRATION_DIALOG_H
+#pragma once
 
 #include <QHBoxLayout>
 #include <QMessageBox>
@@ -29,5 +28,3 @@ private:
 
     QAbstractButton* m_clickedButton;
 };
-
-#endif // MIGRATION_DIALOG_H