[*] 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/tools/renderdoc.cpp

@@ -31,7 +31,7 @@ RenderdocAPI::RenderdocAPI() {
 #elif defined(__HAIKU__)
     // no rtld on haiku
 #else
-#ifdef ANDROID
+#ifdef __ANDROID__
     static constexpr const char RENDERDOC_LIB[] = "libVkLayer_GLES_RenderDoc.so";
 #else
     static constexpr const char RENDERDOC_LIB[] = "librenderdoc.so";