[Ada] Missing finalization on generic instantiation

[Ada] Missing finalization on generic instantiation

gcc/ada/

	* exp_ch7.adb (Build_Finalizer_Helper.New_Finalizer_Name):
	Unnest so that it can be reused.
	(Build_Finalizer_Helper.Process_Declarations): Call the
	xxx__finalize_body procedure of a package instantiation in case
	it contains finalization statements.  Code clean ups.
	(Build_Finalizer_Helper.Create_Finalizer): Export and set an
	Interface_Name for library level finalizers since these may be
	imported now.
	(Build_Finalizer_Helper): Need to process library level package
	body instantiations which may contain objects requiring
	finalization.
	* libgnat/s-finmas.ads: Fix typo.