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

openair2/NR_PHY_INTERFACE/NR_IF_Module.c

@@ -203,7 +203,7 @@ static void handle_nr_ulsch(NR_UL_IND_t *UL_info)
                 crc->timing_advance,
                 crc->ul_cqi,
                 crc->rssi);
-      handle_nr_ul_harq(UL_info->CC_id, UL_info->module_id, UL_info->frame, UL_info->slot, crc);
+      handle_nr_ul_harq(UL_info->module_id, UL_info->frame, UL_info->slot, crc);
     }
     UL_info->rx_ind.number_of_pdus = 0;
     UL_info->crc_ind.number_crcs = 0;