add VTY port number for osmo-stp

Change-Id: I978e1b73aa8097a7db6318d78f9f93457e6ce2af
diff --git a/include/osmocom/vty/ports.h b/include/osmocom/vty/ports.h
index 887e4df..a6043b3 100644
--- a/include/osmocom/vty/ports.h
+++ b/include/osmocom/vty/ports.h
@@ -9,6 +9,7 @@
  */
 
 /* 4238 used by osmo-bts control interface */
+#define OSMO_VTY_PORT_STP	4239
 #define OSMO_VTY_PORT_PCU	4240	/* also: osmo_pcap_client */
 #define OSMO_VTY_PORT_BTS	4241	/* also: osmo_pcap_server */
 #define OSMO_VTY_PORT_NITB_BSC	4242