gprs_ns2: add signalling & data weights for UDP binds

Allow to assign a signalling and data weight to UDP binds.
Those weights will be used when doing dynamic configuration over
IP-SNS.
This is only the first part which only uses the assigned weights
when doing a new SNS configuration.
The outgoing change weight procedure will be supported in a later patch
when the SNS fsm supports outgoing procedures.

Related: SYS#5354
Change-Id: I5133e4229377d44772a9af28628a2bc420fea34b
diff --git a/src/gb/gprs_ns2_internal.h b/src/gb/gprs_ns2_internal.h
index ff95c81..88e352a 100644
--- a/src/gb/gprs_ns2_internal.h
+++ b/src/gb/gprs_ns2_internal.h
@@ -257,6 +257,11 @@
 	void (*dump_vty)(const struct gprs_ns2_vc_bind *bind,
 			 struct vty *vty, bool stats);
 
+	/*! the IP-SNS signalling weight when doing dynamic configuration */
+	uint8_t sns_sig_weight;
+	/*! the IP-SNS data weight when doing dynamic configuration */
+	uint8_t sns_data_weight;
+
 	struct osmo_stat_item_group *statg;
 };
 
@@ -352,6 +357,7 @@
 					     const char *id);
 void ns2_sns_replace_nsvc(struct gprs_ns2_vc *nsvc);
 void ns2_sns_notify_alive(struct gprs_ns2_nse *nse, struct gprs_ns2_vc *nsvc, bool alive);
+void ns2_sns_update_weights(struct gprs_ns2_vc_bind *bind);
 
 /* vc */
 struct osmo_fsm_inst *ns2_vc_fsm_alloc(struct gprs_ns2_vc *nsvc,