linux/ip:close all TLS sessions on n/w i/f change

Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>

port/linux/ipadapter.c

@@ -645,6 +645,7 @@ process_interface_change_event(void)
   }
 
   if (if_state_changed) {
+    oc_close_all_tls_sessions();
     for (i = 0; i < num_devices; i++) {
       ip_context_t *dev = get_ip_context_for_device(i);
       oc_network_event_handler_mutex_lock();