mlua-sys: Fix luau-codegen feature flag usage

Author: khvzak

mlua-sys/src/luau/mod.rs

@@ -4,6 +4,7 @@ pub use compat::*;
 pub use lauxlib::*;
 pub use lua::*;
 pub use luacode::*;
+#[cfg(any(feature = "luau-codegen", doc))]
 pub use luacodegen::*;
 pub use lualib::*;
 pub use luarequire::*;
@@ -12,6 +13,8 @@ pub mod compat;
 pub mod lauxlib;
 pub mod lua;
 pub mod luacode;
+#[cfg(any(feature = "luau-codegen", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau-codegen")))]
 pub mod luacodegen;
 pub mod lualib;
 pub mod luarequire;