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/vty.h b/include/osmocom/iuh/vty.h
index 905a949..3d05da5 100644
--- a/include/osmocom/iuh/vty.h
+++ b/include/osmocom/iuh/vty.h
@@ -5,5 +5,7 @@
 enum osmo_iuh_vty_node {
 	HNBGW_NODE = _LAST_OSMOVTY_NODE + 1,
 	IUH_NODE,
+	IUCS_NODE,
+	IUPS_NODE,
 };