Merge pull request #250 from rust-osdev/const_fn_trait_bound

Use new `const_fn_trait_bound` feature to fix build on latest nightly

Author: phil-opp

src/lib.rs

@@ -2,10 +2,10 @@
 //! and access to various system registers.
 
 #![cfg_attr(not(test), no_std)]
-#![cfg_attr(feature = "const_fn", feature(const_fn))] // Needed for generic access to associated consts
 #![cfg_attr(feature = "const_fn", feature(const_panic))]
 #![cfg_attr(feature = "const_fn", feature(const_mut_refs))]
 #![cfg_attr(feature = "const_fn", feature(const_fn_fn_ptr_basics))]
+#![cfg_attr(feature = "const_fn", feature(const_fn_trait_bound))]
 #![cfg_attr(feature = "inline_asm", feature(asm))]
 #![cfg_attr(feature = "abi_x86_interrupt", feature(abi_x86_interrupt))]
 #![warn(missing_docs)]