[rr] Fix handling on maddr param in RURI

If present in RURI, maddr value should be considered (instead of host part) for testing if RURI points (as domain) to OpenSIPS or not (the is_myselg() test)

(cherry picked from commit f3cb92d)

modules/rr/loose.c

@@ -232,10 +232,13 @@ static inline int is_myself(struct sip_uri* _uri)
 	int ret;
 	unsigned short port;
 	unsigned short proto;
+	str *host;
 
 	port = get_uri_port(_uri, &proto);
+	host = (_uri->maddr.s && _uri->maddr_val.s) ?
+		&_uri->maddr_val : &_uri->host;
 
-	ret = check_self(&_uri->host, port, proto);
+	ret = check_self( host, port, proto);
 	if (ret < 0) return 0;
 
 #ifdef ENABLE_USER_CHECK