PR c++/92552 - ICE with inherited constrained default ctor.
We set TYPE_HAS_USER_CONSTRUCTOR on the template type in lookup_using_decl,
but we didn't copy it to the instantiation. Setting it in
one_inherited_ctor is too late, as that gets called after we decide whether
to set CLASSTYPE_LAZY_DEFAULT_CTOR. This change affects other testcases as
well; the changes are fixes for the other inherited constructor tests as
well.
* pt.c (instantiate_class_template_1): Copy
TYPE_HAS_USER_CONSTRUCTOR.
* class.c (one_inherited_ctor): Don't set it here.