ada: Fix missing finalization in library-level instance body

ada: Fix missing finalization in library-level instance body

This extends the delaying mechanism present in the cases where the instance
is not at library level, so as to wait until after the instantiation of the
body is performed, before generating the finalizer of the compilation unit.

gcc/ada/

	* einfo.ads (Delay_Cleanups): Document new usage.
	* exp_ch7.ads (Build_Finalizer): New declaration.
	* exp_ch7.adb (Build_Finalizer.Process_Declarations): Do not treat
	library-level package instantiations specially.
	(Build_Finalizer): Return early for package bodies and specs that
	are not compilation units instead of using a more convoluted test.
	(Expand_N_Package_Body): Do not build a finalizer if Delay_Cleanups
	is set on the defining entity.
	(Expand_N_Package_Declaration): Likewise.
	* inline.ads (Pending_Body_Info): Reorder and add Fin_Scop.
	(Add_Pending_Instantiation): Add Fin_Scop parameter.
	* inline.adb (Add_Pending_Instantiation): Likewise and copy it into
	the Pending_Body_Info appended to Pending_Instantiations.
	(Add_Scope_To_Clean): Change parameter name to Scop and remove now
	irrelevant processing.
	(Cleanup_Scopes): Deal with scopes that are package specs or bodies.
	(Instantiate_Body): For package instantiations, deal specially with
	scopes that are package bodies and with scopes that are dynamic.
	Pass the resulting scope to Add_Scope_To_Clean directly.
	* sem_ch12.adb (Analyze_Package_Instantiation): In the case where a
	body is needed, compute the enclosing finalization scope and pass it
	in the call to Add_Pending_Instantiation.
	(Inline_Instance_Body): Adjust aggregate passed in the calls to
	Instantiate_Package_Body.
	(Load_Parent_Of_Generic): Likewise.