* lexsup.c (parse_args): Add support for new options -( -) with

	* lexsup.c (parse_args): Add support for new options -( -) with
	synonyms --start-group --end-group.
	* ldlang.h (enum statement_enum): Add lang_group_statement_enum.
	(lang_group_statement_type): Define new struct.
	(lang_statement_union_type): Add group_statement field.
	(lang_enter_group, lang_leave_group): Declare.
	* ldlang.c (lang_for_each_statement_worker): Handle
	lang_group_statement_enum.
	(map_input_to_output_sections, print_statement): Likewise.
	(lang_size_sections, lang_do_assignments): Likewise.
	(open_input_bfds): Completely rewrite.  Now does its own looping,
	rather than using lang_for_each_statement.  Handle groups.
	(lang_process): Update call to open_input_bfds.
	(print_group): New static function.
	(lang_enter_group, lang_leave_group): New static functions.
	* ldfile.c (ldfile_open_file): If the file has already been
	opened, just return rather than taking an assertion failure.
	* ldver.c (help): Mention new options.
	* ld.texinfo: Document new options.