Fix MNCC for the NOKIA BTS type

(thanks to Gus Bourg)
diff --git a/openbsc/src/libmsc/gsm_04_08.c b/openbsc/src/libmsc/gsm_04_08.c
index b0bfeca..bd452ed 100644
--- a/openbsc/src/libmsc/gsm_04_08.c
+++ b/openbsc/src/libmsc/gsm_04_08.c
@@ -1705,6 +1705,7 @@
 		break;
 	case GSM_BTS_TYPE_BS11:
 	case GSM_BTS_TYPE_RBS2000:
+	case GSM_BTS_TYPE_NOKIA_SITE:
 		if (enable)
 			return trau_recv_lchan(lchan, callref);
 		return trau_mux_unmap(NULL, callref);
@@ -2990,6 +2991,7 @@
 			return rtp_send_frame(trans->conn->lchan->abis_ip.rtp_socket, arg);
 		case GSM_BTS_TYPE_BS11:
 		case GSM_BTS_TYPE_RBS2000:
+		case GSM_BTS_TYPE_NOKIA_SITE:
 			return trau_send_frame(trans->conn->lchan, arg);
 		default:
 			LOGP(DCC, LOGL_ERROR, "Unknown BTS type %u\n", bts->type);