Add missing fields to _outConstraint()

Add missing fields to _outConstraint()

As of 897795240cfaaed724af2f53ed2c50c9862f951f, check constraints can
be declared invalid.  But that patch didn't update _outConstraint() to
also show the relevant struct fields (which were only applicable to
foreign keys before that).  This currently only affects debugging
output, so no impact in practice.