PR c++/68290
	* constraint.cc (make_constrained_auto): Move to...
	* pt.c (make_auto_1): Add set_canonical parameter and set
	TYPE_CANONICAL on the type only if it is true.
	(make_decltype_auto): Adjust call to make_auto_1.
	(make_auto): Likewise.
	(splice_late_return_type): Likewise.
	(make_constrained_auto): ...here.  Call make_auto_1 instead of
	make_auto and pass false.  Set TYPE_CANONICAL directly.

From-SVN: r231189