Fix more unused imports errors.

Author: iancormac84

src/librustc/ty/util.rs

@@ -24,8 +24,7 @@ use ty::layout::{Integer, IntegerExt};
 use util::common::ErrorReported;
 use middle::lang_items;
 
-use rustc_data_structures::stable_hasher::{StableHasher, StableHasherResult,
-                                           HashStable};
+use rustc_data_structures::stable_hasher::{StableHasher, HashStable};
 use rustc_data_structures::fx::FxHashMap;
 use std::{cmp, fmt};
 use syntax::ast;