* cond.c (s_ifdef): If we should omit conditionals from listings,

	* cond.c (s_ifdef): If we should omit conditionals from listings,
	call listing_list.
	(s_if, s_ifc, s_endif, s_else, s_ifeqs): Likewise.
	* listing.c (list_info_struct): Add EDICT_NOLIST_NEXT.
	(listing_listing): Handle EDICT_NOLIST_NEXT.
	(listing_list): An argument of 2 means EDICT_NOLIST_NEXT.
	* listing.h (LISTING_NOCOND): Define.
	(LISTING_SKIP_COND): Define.
	* as.c (show_usage): Mention c as a suboption of -a.
	(parse_args): Handle c as a suboption of -a.
	* doc/as.texinfo: Document -alc.