Named arguments were being passed around by invisible reference, just
not variadic arguments.  There is a need to de-duplicate the routines
that handle declaration/parameter promotion and reference checking.
However for now, the parameter helper functions have just been renamed
to parameter_reference_p and parameter_type, to make it more clear that
it is the Parameter equivalent to declaration_reference_p and
declaration_type.

On writing the tests, a forward-reference bug was discovered on x86_64
during va_list type semantic.  This was due to fields not having their
parent set-up correctly.

gcc/d/ChangeLog:

	PR d/94777
	* d-builtins.cc (build_frontend_type): Set parent for generated
	fields of built-in types.
	* d-codegen.cc (argument_reference_p): Rename to ...
	(parameter_reference_p): ... this.
	(type_passed_as): Rename to ...
	(parameter_type): ... this.  Make TREE_ADDRESSABLE types restrict.
	(d_build_call): Move handling of non-POD types here from ...
	* d-convert.cc (convert_for_argument): ... here.
	* d-tree.h (argument_reference_p): Rename declaration to ...
	(parameter_reference_p): ... this.
	(type_passed_as): Rename declaration to ...
	(parameter_type): ... this.
	* types.cc (TypeVisitor::visit (TypeFunction *)): Update caller.

gcc/testsuite/ChangeLog:

	PR d/94777
	* gdc.dg/pr94777a.d: New test.
	* gdc.dg/pr94777b.d: New test.