fix sending of PUBLISH requests (was not set to the proxy address actually)

coreapi/proxy.c

@@ -792,6 +792,7 @@ int linphone_proxy_config_send_publish(LinphoneProxyConfig *proxy,
 			       LinphoneOnlineStatus presence_mode){
 	int err;
 	SalOp *op=sal_op_new(proxy->lc->sal);
+	sal_op_set_route(op,proxy->reg_proxy);
 	err=sal_publish(op,linphone_proxy_config_get_identity(proxy),
 	    linphone_proxy_config_get_identity(proxy),linphone_online_status_to_sal(presence_mode));
 	if (proxy->publish_op!=NULL)

coreapi/sal_eXosip2_presence.c

@@ -635,7 +635,7 @@ int sal_publish(SalOp *op, const char *from, const char *to, SalPresenceStatus p
 
 	mk_presence_body (presence_mode, from, buf, sizeof (buf), presence_style);
 
-	i = eXosip_build_publish(&pub,from, to, NULL, "presence", "300", 
+	i = eXosip_build_publish(&pub,from, to, sal_op_get_route(op), "presence", "300", 
 		presence_style ? "application/xpidf+xml" : "application/pidf+xml", buf);
 	if (i<0){
 		ms_warning("Failed to build publish request.");