BSSGP_Emulation: Implement handling of BVC-UNBLOCK in SGSN role

Change-Id: I7c9cda916f6583613fbf3cdf31f3f08ceadf58d4
diff --git a/library/BSSGP_Emulation.ttcnpp b/library/BSSGP_Emulation.ttcnpp
index 89a69ad..2a87b35 100644
--- a/library/BSSGP_Emulation.ttcnpp
+++ b/library/BSSGP_Emulation.ttcnpp
@@ -977,6 +977,12 @@
 		f_ptp_change_state(BVC_S_UNBLOCKED);
 	}
 
+	/* Inbound  BVC-UNBLOCK from peer */
+	[g_sgsn_role] BVC.receive(tr_ptp_BnsUdInd(t_BVC_UNBLOCK(g_cfg.bvci), 0)) {
+		BVC.send(ts_ptp_BnsUdReq(t_BVC_UNBLOCK_ACK(g_cfg.bvci), 0, g_bvc_lsp));
+		f_ptp_change_state(BVC_S_UNBLOCKED);
+	}
+
 	/* RESET-ACK before T2 timeout: reset successful. In SGSN role, CellID must be present */
 	[g_T2.running and g_sgsn_role] BVC.receive(tr_ptp_BnsUdInd(tr_BVC_RESET_ACK(g_cfg.bvci, g_cfg.cell_id), 0)) -> value udi {
 		g_T2.stop;