Avoid using file_stat in liboctave/util (bug #59711). * cmd-edit.cc (looks_like_filename), cmd-hist.cc (gnu_history::do_append), kpse.cc (kpse_element_dir), oct-glob.cc (glob, windows_glob), url-transfer.cc (base_url_transfer::mget_directory): Use functions "dir_exists" or "file_exists" instead of "file_stat". * kpse.cc (dir_p), oct-glob.cc (single_match_exists): Remove unused static functions.