Bugfix: only fill DU system information if SA

In NSA, we don't have SIB1. However, the DU system information requires
both MIB and SIB1, but is itself optional. So, in NSA, don't fill the DU
system information.

openair2/GNB_APP/gnb_config.c

@@ -1153,18 +1153,20 @@ static f1ap_setup_req_t *RC_read_F1Setup(uint64_t id,
 
   req->cell[0].info.measurement_timing_information = "0";
 
-  int buf_len = 3; // this is what we assume in monolithic
-  req->cell[0].sys_info = calloc(1, sizeof(*req->cell[0].sys_info));
-  AssertFatal(req->cell[0].sys_info != NULL, "out of memory\n");
-  f1ap_gnb_du_system_info_t *sys_info = req->cell[0].sys_info;
-  sys_info->mib = calloc(buf_len, sizeof(*sys_info->mib));
-  DevAssert(sys_info->mib != NULL);
-  DevAssert(mib != NULL);
-  sys_info->mib_length = encode_MIB_NR(mib, 0, sys_info->mib, buf_len);
-  DevAssert(sys_info->mib_length == buf_len);
-
   if (get_softmodem_params()->sa) {
-    // in NSA we don't transmit SIB1
+    // in NSA we don't transmit SIB1, so cannot fill DU system information
+    // so cannot send MIB either
+
+    int buf_len = 3; // this is what we assume in monolithic
+    req->cell[0].sys_info = calloc(1, sizeof(*req->cell[0].sys_info));
+    AssertFatal(req->cell[0].sys_info != NULL, "out of memory\n");
+    f1ap_gnb_du_system_info_t *sys_info = req->cell[0].sys_info;
+    sys_info->mib = calloc(buf_len, sizeof(*sys_info->mib));
+    DevAssert(sys_info->mib != NULL);
+    DevAssert(mib != NULL);
+    sys_info->mib_length = encode_MIB_NR(mib, 0, sys_info->mib, buf_len);
+    DevAssert(sys_info->mib_length == buf_len);
+
     DevAssert(sib1 != NULL);
     NR_SIB1_t *bcch_SIB1 = sib1->message.choice.c1->choice.systemInformationBlockType1;
     sys_info->sib1 = calloc(NR_MAX_SIB_LENGTH / 8, sizeof(*sys_info->sib1));