GUACAMOLE-525: Fix up password history delete to be more compatible.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/resources/org/apache/guacamole/auth/jdbc/user/PasswordRecordMapper.xml

@@ -65,12 +65,11 @@
         );
 
         DELETE FROM [guacamole_user_password_history]
-        WHERE password_history_id IN (
-            SELECT password_history_id
+        WHERE password_history_id NOT IN (
+            SELECT TOP(#{maxHistorySize}) password_history_id
             FROM [guacamole_user_password_history]
             WHERE user_id = #{record.userID,jdbcType=INTEGER}
             ORDER BY password_date DESC
-            OFFSET #{maxHistorySize}
         );
 
     </insert>