Merge pull request #4 from chebykinn/fix-ahcid

Fix missing use statement

ahcid/src/ahci/hba.rs

@@ -1,6 +1,6 @@
 use std::mem::size_of;
 use std::ops::DerefMut;
-use std::{ptr, u32};
+use std::{ptr, u32, thread};
 
 use syscall::io::{Dma, Io, Mmio};
 use syscall::error::{Error, Result, EIO};