[Ada] Exp_Util: minor refactoring

2019-07-09  Piotr Trojanek  <trojanek@adacore.com>

gcc/ada/

	* exp_util.adb (Containing_Package_With_Ext_Axioms): Replace
	low-level Ekind test with a high-level wrapper.

From-SVN: r273285

gcc/ada/ChangeLog

+2019-07-09  Piotr Trojanek  <trojanek@adacore.com>
+
+	* exp_util.adb (Containing_Package_With_Ext_Axioms): Replace
+	low-level Ekind test with a high-level wrapper.
+
 2019-07-09  Arnaud Charlet  <charlet@adacore.com>
 
 	* libgnat/s-memory.adb: Disable calls to Abort defer/undefer

gcc/ada/exp_util.adb

@@ -4492,7 +4492,7 @@ package body Exp_Util is
    begin
       --  E is the package or generic package which is externally axiomatized
 
-      if Ekind_In (E, E_Generic_Package, E_Package)
+      if Is_Package_Or_Generic_Package (E)
         and then Has_Annotate_Pragma_For_External_Axiomatization (E)
       then
          return E;