[Ada] Replace low-level membership tests with high-level routines

Code cleanup to improve readablity. Semantics unaffected.

2019-08-21  Piotr Trojanek  <trojanek@adacore.com>

gcc/ada/

	* exp_util.adb (Corresponding_Runtime_Package): Use high-level
	Is_Protected_Type.
	* sem_ch8.adb (Analyze_Renamed_Entry): Likewise.
	* sem_ch9.adb (Analyze_Requeue): Likewise.

From-SVN: r274777

gcc/ada/ChangeLog

+2019-08-21  Piotr Trojanek  <trojanek@adacore.com>
+
+	* exp_util.adb (Corresponding_Runtime_Package): Use high-level
+	Is_Protected_Type.
+	* sem_ch8.adb (Analyze_Renamed_Entry): Likewise.
+	* sem_ch9.adb (Analyze_Requeue): Likewise.
+
 2019-08-21  Javier Miranda  <miranda@adacore.com>
 
 	* sem_util.adb (Update_Named_Associations): Update

gcc/ada/exp_util.adb

@@ -4609,7 +4609,7 @@ package body Exp_Util is
    begin
       pragma Assert (Is_Concurrent_Type (Typ));
 
-      if Ekind (Typ) in Protected_Kind then
+      if Is_Protected_Type (Typ) then
          if Has_Entries (Typ)
 
             --  A protected type without entries that covers an interface and

gcc/ada/sem_ch8.adb

@@ -1696,7 +1696,7 @@ package body Sem_Ch8 is
       --  AI05-0225: If the renamed entity is a procedure or entry of a
       --  protected object, the target object must be a variable.
 
-      if Ekind (Scope (Old_S)) in Protected_Kind
+      if Is_Protected_Type (Scope (Old_S))
         and then Ekind (New_S) = E_Procedure
         and then not Is_Variable (Prefix (Nam))
       then

gcc/ada/sem_ch9.adb

@@ -2350,8 +2350,7 @@ package body Sem_Ch9 is
          for S in reverse 0 .. Scope_Stack.Last loop
             Req_Scope := Scope_Stack.Table (S).Entity;
 
-            exit when Ekind (Req_Scope) in Task_Kind
-              or else Ekind (Req_Scope) in Protected_Kind;
+            exit when Is_Concurrent_Type (Req_Scope);
 
             if Is_Entry (Req_Scope) then
                Outer_Ent := Req_Scope;