[GPRS] NS: VTY: Move all local ip/port bind values into 'ns' node

This removes the requirement for gb_proxy and sgsn to have duplicate
vty parsing code
diff --git a/openbsc/include/openbsc/gprs_ns.h b/openbsc/include/openbsc/gprs_ns.h
index 319ff3d..1ec6631 100644
--- a/openbsc/include/openbsc/gprs_ns.h
+++ b/openbsc/include/openbsc/gprs_ns.h
@@ -134,10 +134,14 @@
 	/* NS-over-IP specific bits */
 	struct {
 		struct bsc_fd fd;
+		uint32_t local_ip;
+		uint16_t local_port;
 	} nsip;
 	/* NS-over-FR-over-GRE-over-IP specific bits */
 	struct {
 		struct bsc_fd fd;
+		uint32_t local_ip;
+		int enabled:1;
 	} frgre;
 };
 
@@ -188,7 +192,7 @@
 void gprs_ns_destroy(struct gprs_ns_inst *nsi);
 
 /* Listen for incoming GPRS packets via NS/UDP */
-int nsip_listen(struct gprs_ns_inst *nsi, uint32_t ip, uint16_t udp_port);
+int gprs_ns_nsip_listen(struct gprs_ns_inst *nsi);
 
 struct sockaddr_in;
 
@@ -200,7 +204,7 @@
 int gprs_ns_tx_unblock(struct gprs_nsvc *nsvc);
 
 /* Listen for incoming GPRS packets via NS/FR/GRE */
-int gprs_ns_frgre_listen(struct gprs_ns_inst *nsi, uint32_t ip);
+int gprs_ns_frgre_listen(struct gprs_ns_inst *nsi);
 
 /* Establish a connection (from the BSS) to the SGSN */
 struct gprs_nsvc *nsip_connect(struct gprs_ns_inst *nsi,