use c++ instead of _stat for copy_node_stat

use c++ instead of _stat for copy_node_stat

gcc/cp/ChangeLog:

2017-07-28  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>

	* lex.c (copy_decl): Adjust.
	(copy_type): Likewise.

gcc/ChangeLog:

2017-07-28  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>

	* tree.c (copy_node_stat): Rename to copy_node.
	(build_distinct_type_copy): Adjust.
	* tree.h (copy_node_stat): Adjust prototype.
	(copy_node): Remove macro.

From-SVN: r250695