corex: fix name in the example for send_data() function

modules/corex/README

@@ -288,7 +288,7 @@ modparam("corex", "msg_avp", "$avp(msg)")
 
    Example 1.7. send_data usage
 ...
-        send("sip:example.com:5070;transport=sctp", "Message at $Ts");
+        send_data("sip:example.com:5070;transport=sctp", "Message at $Ts");
 ...
 
 4.5. is_incoming()

modules/corex/doc/corex_admin.xml

@@ -267,7 +267,7 @@ modparam("corex", "msg_avp", "$avp(msg)")
 		<title><function>send_data</function> usage</title>
 		<programlisting format="linespecific">
 ...
-	send("sip:example.com:5070;transport=sctp", "Message at $Ts");
+	send_data("sip:example.com:5070;transport=sctp", "Message at $Ts");
 ...
 </programlisting>
 		</example>