Fix --help=target (PR other/39851).

2017-08-29  Martin Liska  <mliska@suse.cz>

	PR other/39851
	* gcc.c (driver_handle_option): Add new argument.
	* opts-common.c (handle_option): Pass
	target_option_override_hook.
	* opts-global.c (lang_handle_option): Add new option.
	(set_default_handlers):  Add new argument.
	(decode_options): Likewise.
	* opts.c (target_handle_option): Likewise.
	(common_handle_option): Call target_option_override_hook.
	* opts.h (struct cl_option_handler_func): Add hook for
	target option override.
	(struct cl_option_handlers): Likewise.
	(set_default_handlers): Add new argument.
	(decode_options): Likewise.
	(common_handle_option): Likewise.
	(target_handle_option): Likewise.
	* toplev.c (toplev::main): Pass targetm.target_option.override
	hook.
2017-08-29  Martin Liska  <mliska@suse.cz>

	PR other/39851
	* c-common.c (parse_optimize_options): Add argument to function
	call.
	* c-pragma.c (handle_pragma_diagnostic): Likewise.

From-SVN: r251400