ada: Fix double finalization in conditional exit statement

The temporary is first finalized through its enclosing block.

gcc/ada/

	* exp_ch4.adb (Expand_N_Expression_With_Actions.Process_Action): Do
	not look into nested blocks.

Tested on x86_64-pc-linux-gnu, committed on master.

gcc/ada/exp_ch4.adb

@@ -5651,14 +5651,17 @@ package body Exp_Ch4 is
             return Skip;
 
          --  Avoid processing temporary function results multiple times when
-         --  dealing with nested expression_with_actions.
+         --  dealing with nested expression_with_actions or nested blocks.
          --  Similarly, do not process temporary function results in loops.
          --  This is done by Expand_N_Loop_Statement and Build_Finalizer.
          --  Note that we used to wrongly return Abandon instead of Skip here:
          --  this is wrong since it means that we were ignoring lots of
          --  relevant subsequent statements.
 
-         elsif Nkind (Act) in N_Expression_With_Actions | N_Loop_Statement then
+         elsif Nkind (Act) in N_Expression_With_Actions
+                            | N_Block_Statement
+                            | N_Loop_Statement
+         then
             return Skip;
          end if;