hnbgw: parameterize IuCS and IuPS ips and ports: add vty cmds

Basically copy-paste the Iuh local-ip and local-port code to provide
parameterization of the IuCS and IuPS remote addresses.

Add IUCS and IUPS nodes, enhance go_parent_cb and config writing accordingly.

Change-Id: I2c28977011009df4e1fa472290bbbc359e406971
diff --git a/include/osmocom/iuh/hnbgw.h b/include/osmocom/iuh/hnbgw.h
index 850c4d9..4880d48 100644
--- a/include/osmocom/iuh/hnbgw.h
+++ b/include/osmocom/iuh/hnbgw.h
@@ -20,6 +20,8 @@
 
 
 #define HNBGW_LOCAL_IP_DEFAULT "0.0.0.0"
+#define HNBGW_IUCS_REMOTE_IP_DEFAULT "127.0.0.1"
+#define HNBGW_IUPS_REMOTE_IP_DEFAULT "127.0.0.2"
 
 /* 25.467 Section 7.1 */
 #define IUH_DEFAULT_SCTP_PORT	29169
@@ -116,6 +118,10 @@
 		/*! The UDP port where we receive multiplexed CS user
 		 * plane traffic from HNBs */
 		uint16_t iuh_cs_mux_port;
+		const char *iucs_remote_ip;
+		uint16_t iucs_remote_port;
+		const char *iups_remote_ip;
+		uint16_t iups_remote_port;
 		uint16_t rnc_id;
 		bool hnbap_allow_tmsi;
 	} config;