[*] 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/common/fs/file.cpp

@@ -9,7 +9,7 @@
 #include "common/assert.h"
 #include "common/fs/file.h"
 #include "common/fs/fs.h"
-#ifdef ANDROID
+#ifdef __ANDROID__
 #include "common/fs/fs_android.h"
 #endif
 #include "common/logging.h"
@@ -259,7 +259,7 @@ void IOFile::Open(const fs::path& path, FileAccessMode mode, FileType type, File
     } else {
         _wfopen_s(&file, path.c_str(), AccessModeToWStr(mode, type));
     }
-#elif ANDROID
+#elif __ANDROID__
     if (Android::IsContentUri(path)) {
         ASSERT_MSG(mode == FileAccessMode::Read, "Content URI file access is for read-only!");
         const auto fd = Android::OpenContentUri(path, Android::OpenMode::Read);
@@ -396,7 +396,7 @@ u64 IOFile::GetSize() const {
     // Flush any unwritten buffered data into the file prior to retrieving the file size.
     std::fflush(file);
 
-#if ANDROID
+#ifdef __ANDROID__
     u64 file_size = 0;
     if (Android::IsContentUri(file_path)) {
         file_size = Android::GetSize(file_path);