acle/barrier: remove cfg from re-export

addresses rust-lang/stdarch#557 (comment)

Author: japaric

library/stdarch/crates/core_arch/src/acle/mod.rs

@@ -41,11 +41,6 @@
 // via CP15 instructions. See Section 10.1 of ACLE
 mod barrier;
 
-#[cfg(any(
- target_arch = "aarch64",
- target_feature = "v7",
- target_feature = "mclass"
-))]
 pub use self::barrier::*;
 
 mod hints;