Add hipri to ATT Phone APN

per http://www.att.com/esupport/article.jsp?sid=KB424489&cv=820

Change-Id: Ib6552dd6358e2198f9e1da8420cc72da1664c606

prebuilt/common/etc/apns-conf.xml

@@ -718,7 +718,7 @@
   <apn carrier="AWS MMS" mcc="310" mnc="380" apn="proxy" mmsc="http://mmsc.mymmode.com" mmsproxy="10.250.250.55" mmsport="8080" type="mms" />
   <apn carrier="Celloneet MMS" mcc="310" mnc="390" apn="mms.celloneet.com" user="user1@mms.celloneet.com" password="celloneet" mmsc="http://mms.celloneet.com/servlets/mms" mmsproxy="63.99.231.135" mmsport="8080" type="mms" />
   <apn carrier="ATT" mcc="310" mnc="410" apn="wap.cingular" user="WAP@CINGULARGPRS.COM" mmsc="http://mmsc.cingular.com" mmsproxy="wireless.cingular.com" mmsport="80" type="default,supl,mms" />
-  <apn carrier="ATT Phone" mcc="310" mnc="410" apn="phone" mmsc="http://mmsc.mobile.att.net" mmsproxy="proxy.mobile.att.net" mmsport="80" type="default,supl,mms" />
+  <apn carrier="ATT Phone" mcc="310" mnc="410" apn="phone" mmsc="http://mmsc.mobile.att.net" mmsproxy="proxy.mobile.att.net" mmsport="80" type="default,supl,mms,hipri" />
   <apn carrier="ATT LTE" mcc="310" mnc="410" apn="pta" mmsc="http://mmsc.mobile.att.net" mmsproxy="proxy.mobile.att.net" mmsport="80" type="default,supl,mms" />
   <apn carrier="ATT Broadband" mcc="310" mnc="410" apn="broadband" user="" server="" password="" mmsc="" type="default" />
   <apn carrier="ATT Activation" mcc="310" mnc="410" apn="lwaactivate" user="" server="" password="" mmsc="" protocol="IP" />