[Ada] Missing finalization of private protected type

[Ada] Missing finalization of private protected type

This patch updates the analysis of protected types to properly mark the
type as having controlled components when it contains at least one such
component. This in turn marks a potential partial view as requiring
finalization actions.

------------
-- Source --
------------

--  types.ads

with Ada.Finalization; use Ada.Finalization;

package Types is
   type Ctrl_Typ is new Controlled with null record;
   procedure Finalize (Obj : in out Ctrl_Typ);

   type Prot_Typ is limited private;

private
   protected type Prot_Typ is
   private
      Comp : Ctrl_Typ;
   end Prot_Typ;
end Types;

--  types.adb

with Ada.Text_IO; use Ada.Text_IO;

package body Types is
   procedure Finalize (Obj : in out Ctrl_Typ) is
   begin
      Put_Line ("finalize");
   end Finalize;

   protected body Prot_Typ is
   end Prot_Typ;
end Types;

--  main.adb

with Types; use Types;

procedure Main is
   Obj : Prot_Typ;
begin
   null;
end Main;

2019-07-11  Hristian Kirtchev  <kirtchev@adacore.com>

gcc/ada/

	* exp_util.ads, exp_util.adb (Needs_Finalization): Move to
	Sem_Util.
	* sem_ch9.adb (Analyze_Protected_Definition): Code cleanup. Mark
	the protected type as having controlled components when it
	contains at least one such component.
	* sem_util.ads, sem_util.adb (Needs_Finalization): New
	function.

From-SVN: r273383