Convert declarations or definitions to standard C.

Convert declarations or definitions to standard C.
* src/xsmfns.c (smc_save_yourself_CB, smc_error_handler):
* src/xrdb.c (get_system_name):
* src/window.c (shrink_windows):
* src/syntax.c (forw_comment):
* src/scroll.c (calculate_scrolling, calculate_direct_scrolling)
(ins_del_costs):
* src/mem-limits.h (start_of_data):
* src/lread.c (readevalloop):
* src/gtkutil.c (xg_dialog_response_cb, xg_get_file_with_chooser)
(xg_get_file_with_selection, xg_update_menubar, xg_update_submenu):
* src/frame.c (x_get_focus_frame):
* src/floatfns.c (fmod_float):
* src/fileio.c (choose_write_coding_system):
* src/emacs.c (fatal_error_signal, init_cmdargs, argmatch)
(malloc_initialize_hook, sort_args, synchronize_locale):
* src/doprnt.c (doprnt):
* src/dired.c (compile_pattern):
* src/data.c (fmod_float):
* src/chartab.c (map_sub_char_table, map_sub_char_table_for_charset)
(map_char_table_for_charset):
* src/charset.c (define_charset_internal):
* src/alloc.c (Fgarbage_collect): Convert declarations or definitions
to standard C.