message: fuzz: don't try and use fopencookie when building for Android
  When building for Android, _GNU_SOURCE will be defined, but it doesn't
  actually have the fopencookie() function, or define the
  cookie_io_functions_t type.
  For now just skip trying to use it if we are building for Android.
  Should fix
diff: @@ -384,7 +384,7 @@ public:
  [&] {
  mode = "a+";
  });
  -#ifdef _GNU_SOURCE
  +#if defined _GNU_SOURCE && !defined __ANDROID__
  const cookie_io_functions_t io_hooks = {
  FuzzedFileProvider::read,
  FuzzedFileProvider::write,
  