Mark _Noreturn error functions as cold

Mark _Noreturn error functions as cold

On my platform this made ‘make compile-always’ 1.3% faster.
Suggested by Alex Gramiak in:
https://lists.gnu.org/r/emacs-devel/2019-04/msg00684.html
* configure.ac (nw): Don’t use -Wsuggest-attribute=cold.
* lib-src/make-docfile.c (write_globals):
Mark noreturn functions as cold.
* src/callproc.c (exec_failed):
* src/data.c (wrong_length_argument, wrong_type_argument):
* src/emacs-module.c (module_abort):
* src/emacs.c (terminate_due_to_signal):
* src/eval.c (unwind_to_catch):
* src/image.c (my_png_error, my_error_exit):
* src/json.c (json_out_of_memory, json_parse_error):
* src/keyboard.c (quit_throw_to_read_char, user_error):
* src/lisp.h (die, wrong_type_argument, wrong_choice)
(args_out_of_range, args_out_of_range_3, circular_list)
(buffer_overflow, memory_full, buffer_memory_full)
(string_overflow, xsignal, xsignal0, xsignal1, xsignal2)
(xsignal3, signal_error, overflow_error, error, verror)
(nsberror, report_file_errno, report_file_error)
(report_file_notify_error, terminate_due_to_signal)
(emacs_abort, fatal):
* src/lread.c (load_error_old_style_backquotes)
(end_of_file_error, invalid_syntax):
* src/pdumper.c (error_unsupported_dump_object):
* src/puresize.h (pure_write_error):
* src/search.c (matcher_overflow):
* src/sound.c (sound_perror, alsa_sound_perror):
* src/sysdep.c (handle_arith_signal):
* src/systime.h (time_overflow):
* src/term.c (maybe_fatal, vfatal):
* src/textprop.c (text_read_only):
* src/timefns.c (invalid_time_zone_specification)
(time_error, invalid_hz):
* src/xterm.c (x_connection_closed):
Use AVOID instead of _Noreturn void, so that it’s marked cold.
* src/conf_post.h (__has_attribute_cold) [!__has_attribute]:
New macro.
(ATTRIBUTE_COLD): New macro.
* src/frame.h (WINDOW_SYSTEM_RETURN): Add ATTRIBUTE_COLD.
* src/lisp.h (AVOID): New macro.
* src/xterm.c: Omit unnecessary static decls, so that we needn’t
worry about which functions should be marked cold.
(x_io_error_quitter): Mark as cold.