Auto merge of rust-lang#116033 - bvanjoi:fix-116032, r=petrochenkov

report `unused_import` for empty reexports even it is pub

Fixes rust-lang#116032

An easy fix. r? `@petrochenkov`

(Discovered this issue while reviewing rust-lang#115993.)

Author: bors

src/config/options.rs

@@ -1,3 +1,5 @@
+#![allow(unused_imports)]
+
 use std::collections::{hash_set, HashSet};
 use std::fmt;
 use std::path::{Path, PathBuf};