Remove #[macro_use] extern crate tracing from rustc_parse.

compiler/rustc_parse/src/lexer/mod.rs

@@ -18,6 +18,7 @@ use rustc_session::lint::BuiltinLintDiag;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::Symbol;
 use rustc_span::{edition::Edition, BytePos, Pos, Span};
+use tracing::debug;
 
 mod diagnostics;
 mod tokentrees;

compiler/rustc_parse/src/lexer/unescape_error_reporting.rs

@@ -6,6 +6,7 @@ use std::ops::Range;
 use rustc_errors::{Applicability, DiagCtxt, ErrorGuaranteed};
 use rustc_lexer::unescape::{EscapeError, Mode};
 use rustc_span::{BytePos, Span};
+use tracing::debug;
 
 use crate::errors::{MoreThanOneCharNote, MoreThanOneCharSugg, NoBraceUnicodeSub, UnescapeError};