[Ada] Minor fix grammar in comment of N_Defining_Identifier

2018-05-24  Piotr Trojanek  <trojanek@adacore.com>

gcc/ada/

	* sinfo.ads: Fix grammar in comment.

From-SVN: r260662

gcc/ada/ChangeLog

+2018-05-24  Piotr Trojanek  <trojanek@adacore.com>
+
+	* sinfo.ads: Fix grammar in comment.
+
 2018-05-24  Justin Squirek  <squirek@adacore.com>
 
 	* einfo.ads, einfo.adb (Append_Entity): Modified to use Link_Entities

gcc/ada/sinfo.ads

@@ -2863,7 +2863,7 @@ package Sinfo is
       --  Einfo.
 
       --  Note: N_Defining_Identifier is an extended node whose fields are
-      --  deliberate layed out to match the layout of fields in an ordinary
+      --  deliberately layed out to match the layout of fields in an ordinary
       --  N_Identifier node allowing for easy alteration of an identifier
       --  node into a defining identifier node. For details, see procedure
       --  Sinfo.CN.Change_Identifier_To_Defining_Identifier.