message: use Rust SnakeCase
diff: @@ -10,7 +10,7 @@ use shims::unix::macos::dlsym as macos;
  pub enum Dlsym {
  Linux(linux::Dlsym),
  MacOs(macos::Dlsym),
  - FreeBSD(freebsd::Dlsym),
  + FreeBsd(freebsd::Dlsym),
  }
  impl Dlsym {
  @@ -20,7 +20,7 @@ impl Dlsym {
  Ok(match target_os {
  "linux" => linux::Dlsym::from_str(name)?.map(Dlsym::Linux),
  "macos" => macos::Dlsym::from_str(name)?.map(Dlsym::MacOs),
  - "freebsd" => freebsd::Dlsym::from_str(name)?.map(Dlsym::FreeBSD),
  + "freebsd" => freebsd::Dlsym::from_str(name)?.map(Dlsym::FreeBsd),
  _ => unreachable!(),
  })
  }
  @@ -43,7 +43,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
  match dlsym {
  Dlsym::Linux(dlsym) => linux::EvalContextExt::call_dlsym(this, dlsym, args, dest, ret),
  Dlsym::MacOs(dlsym) => macos::EvalContextExt::call_dlsym(this, dlsym, args, dest, ret),
  - Dlsym::FreeBSD(dlsym) =>
  + Dlsym::FreeBsd(dlsym) =>
  freebsd::EvalContextExt::call_dlsym(this, dlsym, args, dest, ret),
  }
  }
  