updated minicore.rs to include intrinsics feature gate

Author: ricci009

tests/auxiliary/minicore.rs

@@ -17,6 +17,7 @@
 #![feature(no_core, lang_items, rustc_attrs, decl_macro, naked_functions, f16, f128)]
 #![allow(unused, improper_ctypes_definitions, internal_features)]
 #![feature(asm_experimental_arch)]
+#![feature(instrinsics)]
 #![no_std]
 #![no_core]