Don't need the core_intrinsics feature in so many places

Author: Ericson2314

tests/no_std.rs

@@ -1,5 +1,5 @@
 #![cfg(feature="no_std")]
-#![feature(const_fn, core_intrinsics)]
+#![feature(const_fn)]
 
 #![no_std]
 

tests/test.rs

@@ -1,4 +1,4 @@
-#![cfg_attr(feature="nightly", feature(const_fn, core_intrinsics))]
+#![cfg_attr(feature="nightly", feature(const_fn))]
 
 #[macro_use]
 extern crate lazy_static;