ASCI: Add call control for VGCS/VBS

Change-Id: I9947403fde8212b66758104443c60aaacc8b1e7b
Related: OS#4854
diff --git a/include/osmocom/msc/ran_conn.h b/include/osmocom/msc/ran_conn.h
index 7aa50df..cdaa026 100644
--- a/include/osmocom/msc/ran_conn.h
+++ b/include/osmocom/msc/ran_conn.h
@@ -18,9 +18,17 @@
 	uint32_t sccp_conn_id;
 
 	/* MSC role that this RAN connection belongs to. This will be either an msc_i (currently active
-	 * connection) or an msc_t (transitory new connection during Handover). */
+	 * connection) or an msc_t (transitory new connection during Handover).
+	 * Used for usual L3 ran_conn to a subscriber. */
 	struct osmo_fsm_inst *msc_role;
 
+	/* For VGCS/VBS, we have additional N connections to BSS. When receiving messages for a group call peer,
+	 * dispatch to the VGCS management. */
+	struct {
+		void *bss;
+		void *cell;
+	} vgcs;
+
 	bool closing;
 };