fix CVE ref for bug #66060

Author: smalyshev

NEWS

@@ -28,7 +28,8 @@ PHP                                                                        NEWS
   . Fixed bug #61645 (fopen and O_NONBLOCK). (Mike)
 
 - Date:
-  . Fixed bug #66060 (Heap buffer over-read in DateInterval). (Remi)
+  . Fixed bug #66060 (Heap buffer over-read in DateInterval). (CVE-2013-6712) 
+    (Remi)
   . Fixed bug #63391 (Incorrect/inconsistent day of week prior to the year
     1600). (Derick, T. Carter)
   . Fixed bug #61599 (Wrong Day of Week). (Derick, T. Carter)