Use list of UEs during RA instead of array of RA processes

- rewrite add_UE_to_list() and rewrite remove_UE_from_list() to simplify
  list handling
- return pointer from get_new_nr_ue_inst(); it's completely freed by
  delete_nr_ue_data()
- have add_new_UE_RA() add UE context to access list; remove with
  nr_release_ra_UE()
- have add_connected_nr_ue() only add UE to connected list; to move from
  access to connected use transition_ra_connected_nr_ue(); remove with
  mac_remove_nr_ue() as previously
- free memory on problems during RA
- add some documentation
- in NSA/HO: check for pre-configured RA process
- there are asserts in all functions to clarify when a UE has RA

openair1/SIMULATION/NR_PHY/dlsim.c

@@ -185,7 +185,7 @@ int g_mcsIndex = -1, g_mcsTableIdx = 0, g_rbStart = -1, g_rbSize = -1, g_nrOfLay
 void nr_dlsim_preprocessor(module_id_t module_id, frame_t frame, slot_t slot)
 {
   NR_UE_info_t *UE_info = RC.nrmac[module_id]->UE_info.connected_ue_list[0];
-  AssertFatal(RC.nrmac[module_id]->UE_info.connected_ue_list[1] == NULL, "can have only a single UE\n");
+  AssertFatal(RC.nrmac[module_id]->UE_info.connected_ue_list[1] == NULL, "Only single UE allowed in dlsim\n");
   NR_UE_sched_ctrl_t *sched_ctrl = &UE_info->UE_sched_ctrl;
   NR_UE_DL_BWP_t *current_BWP = &UE_info->current_DL_BWP;
   NR_ServingCellConfigCommon_t *scc = RC.nrmac[0]->common_channels[0].ServingCellConfigCommon;
@@ -804,7 +804,7 @@ printf("%d\n", slot);
   N_RB_DL = gNB->frame_parms.N_RB_DL;
   NR_UE_info_t *UE_info = RC.nrmac[0]->UE_info.connected_ue_list[0];
 
-  configure_UE_BWP(RC.nrmac[0], scc, &UE_info->UE_sched_ctrl, NULL, UE_info, -1, -1);
+  configure_UE_BWP(RC.nrmac[0], scc, UE_info, false, -1, -1);
 
   // stub to configure frame_parms
   //  nr_phy_config_request_sim(gNB,N_RB_DL,N_RB_DL,mu,Nid_cell,SSB_positions);