message: Fix copyright header placement
diff: -use alloc::collections::BTreeMap;
  -use core::isize;
  -#[cfg(feature = "newlib")]
  -use core::sync::atomic::AtomicUsize;
  -use core::sync::atomic::{AtomicU32, Ordering};
  -
  // Copyright (c) 2018 Colin Finck, RWTH Aachen University
  //
  // Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
  // http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
  // http://opensource.org/licenses/MIT>, at your option. This file may not be
  // copied, modified, or distributed except according to those terms.
  +
  +use alloc::collections::BTreeMap;
  +use core::isize;
  +#[cfg(feature = "newlib")]
  +use core::sync::atomic::AtomicUsize;
  +use core::sync::atomic::{AtomicU32, Ordering};
  +
  use crate::arch;
  use crate::arch::get_processor_count;
  use crate::arch::percore::*;
  