In FSFS, remove the L1 DAG cache locking parameters.

* subversion/libsvn_fs_fs/tree.c
  (get_dag): Remove NEEDS_LOCK_CACHE parameter.
  (dag_node_cache_get): Same. Update docstring.
  (get_copy_inheritance,
   open_path,
   make_path_mutable): Update callers.
  (get_dag): Remove NEEDS_LOCK_CACHE parameter and update sub-routine calls.
  (svn_fs_fs__node_id,
   fs_node_relation,
   svn_fs_fs__node_created_rev,
   fs_node_created_path,
   fs_node_prop,
   fs_node_proplist,
   fs_props_changed,
   get_root,
   fs_dir_entries,
   copy_helper,
   fs_copied_from,
   fs_file_length,
   fs_file_checksum,
   fs_file_contents,
   fs_try_process_file_contents,
   fs_contents_changed,
   fs_get_file_delta_stream,
   history_prev,
   crawl_directory_dag_for_mergeinfo,
   add_descendant_mergeinfo): Update caller.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1648542 13f79535-47bb-0310-9956-ffa450edef68