Mention OCI8 TAF callback support in UPGRADING

Author: cjbj

UPGRADING

@@ -105,6 +105,9 @@ PHP 7.2 UPGRADE NOTES
 - DBA:
   . Implemented support for the LMDB backend.
 
+- OCI8:
+  . Added Oracle Database Transparent Application Failover (TAF) callback support.
+
 - PCRE:
   . Added `J` modifier for setting PCRE_DUPNAMES.
   . Added `PREG_UNMATCHED_AS_NULL` flag to allow distinguish between unmatched
@@ -218,6 +221,10 @@ See also: https://wiki.php.net/rfc/deprecations_php_7_2
   . Added mb_chr() and mb_ord().
   . Added mb_scurb() that scrub broken multibyte strings.
 
+- OCI8:
+  . Added oci_register_taf_callback() and oci_disable_taf_callback() for
+    Oracle Database TAF callback support.
+
 - Sockets:
   . Added socket_addrinfo_lookup(), socket_addrinfo_connect(),
     socket_addrinfo_bind() and socket_addrinfo_explain().