Makefiles support for rustc_i128 crate

This commit includes manual merge conflict resolution changes from a rebase by @est31.

src/librustc_i128/lib.rs

@@ -9,6 +9,8 @@
 // except according to those terms.
 #![allow(non_camel_case_types)]
 #![cfg_attr(not(stage0), feature(i128_type))]
+#![crate_type="rlib"]
+#![crate_name="rustc_i128"]
 
 #[cfg(stage0)]
 pub type i128 = i64;