[*] 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/core/file_sys/vfs/vfs_real.cpp

@@ -23,7 +23,7 @@
 #define stat _stat64
 #endif
 
-#ifdef ANDROID
+#ifdef __ANDROID__
 #include "common/fs/fs_android.h"
 #endif
 
@@ -288,7 +288,7 @@ RealVfsFile::~RealVfsFile() {
 }
 
 std::string RealVfsFile::GetName() const {
-#ifdef ANDROID
+#ifdef __ANDROID__
     if (path[0] != '/') {
         return FS::Android::GetFilename(path);
     }