* archive.c (SECTION Archives): Update documentation.

	* archive.c (SECTION Archives): Update documentation.
	(_bfd_delete_archive_data): Remove.
	(_bfd_add_bfd_to_archive_cache): Set 'parent_cache' and 'key'.
	(archive_close_worker, _bfd_archive_close_and_cleanup): New
	functions.
	* libbfd-in.h (struct areltdata <parent_cache, key>): New fields.
	(_bfd_delete_archive_data): Don't declare.
	(_bfd_archive_close_and_cleanup): Declare.
	(_bfd_generic_close_and_cleanup): Redefine.
	* libbfd.h: Rebuild.
	* opncls.c (_bfd_delete_bfd): Don't call _bfd_delete_archive_data.
	(bfd_close): Don't close nested thin archives here.