Auto merge of #125105 - nnethercote:rustc_resolve-cleanups, r=estebank

`rustc_resolve` cleanups

Some improvements I found while looking through this code.

r? `@estebank`

compiler/rustc_resolve/src/late.rs

@@ -30,6 +30,7 @@ use rustc_span::source_map::{respan, Spanned};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{BytePos, Span, SyntaxContext};
 use smallvec::{smallvec, SmallVec};
+use tracing::{debug, instrument, trace};
 
 use std::assert_matches::debug_assert_matches;
 use std::borrow::Cow;