* c-ada-spec.c (dump_ada_template): Mark underlying instance type as
	visited.
	(dump_generic_ada_node): Code clean up. Use TREE_VISITED flag to
	decide whether a type has already been declared/seen.
	Do not go to the original type.
	(dump_nested_types): New parameter forward.
	Generate forward declaration if needed and mark type as visited.
	(print_ada_declaration): Call dump_nested_types if not already done.
	Mark types as visited.

From-SVN: r162868