correct the wong commit

Author: Dirreke

src/lib.rs

@@ -17,7 +17,7 @@
     unused_macros,
     unused_macro_rules,
 )]
-// #![cfg_attr(libc_deny_warnings, deny(warnings))]
+#![cfg_attr(libc_deny_warnings, deny(warnings))]
 // Attributes needed when building as part of the standard library
 #![cfg_attr(feature = "rustc-dep-of-std", feature(link_cfg, no_core))]
 #![cfg_attr(libc_thread_local, feature(thread_local))]