Update rustdoc to support #[rustc_auto_trait]

Author: fmease

src/librustdoc/clean/mod.rs

@@ -2793,7 +2793,7 @@ fn clean_maybe_renamed_item<'tcx>(
             ItemKind::Fn(ref sig, generics, body_id) => {
                 clean_fn_or_proc_macro(item, sig, generics, body_id, &mut name, cx)
             }
-            ItemKind::Trait(_, _, generics, bounds, item_ids) => {
+            ItemKind::Trait(_, generics, bounds, item_ids) => {
                 let items = item_ids
                     .iter()
                     .map(|ti| clean_trait_item(cx.tcx.hir().trait_item(ti.id), cx))

src/librustdoc/html/render/span_map.rs

@@ -226,7 +226,7 @@ impl<'tcx> Visitor<'tcx> for SpanMapVisitor<'tcx> {
             | ItemKind::Enum(_, _)
             | ItemKind::Struct(_, _)
             | ItemKind::Union(_, _)
-            | ItemKind::Trait(_, _, _, _, _)
+            | ItemKind::Trait(_, _, _, _)
             | ItemKind::TraitAlias(_, _) => self.extract_info_from_hir_id(item.hir_id()),
             ItemKind::Impl(_)
             | ItemKind::Use(_, _)