Rollup merge of rust-lang#116625 - nnethercote:rustc_hir_pretty, r=fee1-dead

`rustc_hir_pretty` cleanups

Just some improvements I found while looking through this code.

r? ``@fee1-dead``

Author: matthiaskrgr

clippy_lints/src/matches/match_wild_err_arm.rs

@@ -19,7 +19,7 @@ pub(crate) fn check<'tcx>(cx: &LateContext<'tcx>, ex: &Expr<'tcx>, arms: &[Arm<'
     if is_type_diagnostic_item(cx, ex_ty, sym::Result) {
         for arm in arms {
             if let PatKind::TupleStruct(ref path, inner, _) = arm.pat.kind {
-                let path_str = rustc_hir_pretty::to_string(rustc_hir_pretty::NO_ANN, |s| s.print_qpath(path, false));
+                let path_str = rustc_hir_pretty::qpath_to_string(path);
                 if path_str == "Err" {
                     let mut matching_wild = inner.iter().any(is_wild);
                     let mut ident_bind_name = kw::Underscore;

clippy_lints/src/mut_reference.rs

@@ -49,7 +49,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryMutPassed {
                         cx,
                         arguments.iter().collect(),
                         cx.typeck_results().expr_ty(fn_expr),
-                        &rustc_hir_pretty::to_string(rustc_hir_pretty::NO_ANN, |s| s.print_qpath(path, false)),
+                        &rustc_hir_pretty::qpath_to_string(path),
                         "function",
                     );
                 }