c++: Final bit of name-lookup api simplification

We no longer need to give name_lookup_real not name_lookup_nonclass
different names to the name_lookup functions.  This renames the lookup
functions thusly.

	gcc/cp/
	* name-lookup.h (lookup_name_real, lookup_name_nonclass): Rename
	to ...
	(lookup_name): ... these new overloads.
	* name-lookup.c (identifier_type_value_1): Rename lookup_name_real
	call.
	(lookup_name_real_1): Rename to ...
	(lookup_name_1): ... here.
	(lookup_name_real): Rename to ...
	(lookup_name): ... here.  Rename lookup_name_real_1 call.
	(lookup_name_nonclass): Delete.
	* call.c (build_operator_new_call): Rename lookup_name_real call.
	(add_operator_candidates): Likewise.
	(build_op_delete_call): Rename lookup_name_nonclass call.
	* parser.c (cp_parser_lookup_name): Likewise.
	* pt.c (tsubst_friend_class, lookup_init_capture_pack): Likewise.
	(tsubst_expr): Likewise.
	* semantics.c (capture_decltype): Likewise.
	libcc1/
	* libcp1plugin.cc (plugin_build_dependent_expr): Rename
	lookup_name_real call.