[GPRS] add data structures for OML of NSE,CELL,NSVCE

Supporting GPRS means we have a number of additional OML objects to
deal with.  We need to extend our gsm_bts structure to at least
include the nm_state for each of those objects.
diff --git a/openbsc/src/gsm_data.c b/openbsc/src/gsm_data.c
index 6767c3f..de9f4b9 100644
--- a/openbsc/src/gsm_data.c
+++ b/openbsc/src/gsm_data.c
@@ -139,6 +139,7 @@
 			      u_int8_t tsc, u_int8_t bsic)
 {
 	struct gsm_bts *bts = talloc(net, struct gsm_bts);
+	int i;
 
 	if (!bts)
 		return NULL;
@@ -153,6 +154,11 @@
 	INIT_LLIST_HEAD(&bts->trx_list);
 	bts->ms_max_power = 15;	/* dBm */
 
+	for (i = 0; i < ARRAY_SIZE(bts->gprs.nsvc); i++) {
+		bts->gprs.nsvc[i].bts = bts;
+		bts->gprs.nsvc[i].id = i;
+	}
+
 	/* create our primary TRX */
 	bts->c0 = gsm_bts_trx_alloc(bts);
 	if (!bts->c0) {