Fixup sched_ul_bytes logic

1) Only count new transmission as scheduled bytes (which is then
compared against the BSR)

2) When subtracting scheduled bytes after successful reception, subtract
TBsize from correct HARQ process

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c

@@ -432,7 +432,8 @@ void nr_rx_sdu(const module_id_t gnb_mod_idP,
     if (sduP != NULL){
       LOG_D(MAC, "Received PDU at MAC gNB \n");
 
-      UE_scheduling_control->sched_ul_bytes -= UE_info->mac_stats[UE_id].ulsch_current_bytes;
+      const uint32_t tb_size = UE_scheduling_control->ul_harq_processes[harq_pid].sched_pusch.tb_size;
+      UE_scheduling_control->sched_ul_bytes -= tb_size;
       if (UE_scheduling_control->sched_ul_bytes < 0)
         UE_scheduling_control->sched_ul_bytes = 0;
 
@@ -442,7 +443,8 @@ void nr_rx_sdu(const module_id_t gnb_mod_idP,
       NR_UE_ul_harq_t *cur_harq = &UE_scheduling_control->ul_harq_processes[harq_pid];
       /* reduce sched_ul_bytes when cur_harq->round == 3 */
       if (cur_harq->round == 3){
-        UE_scheduling_control->sched_ul_bytes -= UE_info->mac_stats[UE_id].ulsch_current_bytes;
+        const uint32_t tb_size = UE_scheduling_control->ul_harq_processes[harq_pid].sched_pusch.tb_size;
+        UE_scheduling_control->sched_ul_bytes -= tb_size;
         if (UE_scheduling_control->sched_ul_bytes < 0)
           UE_scheduling_control->sched_ul_bytes = 0;
       }
@@ -916,6 +918,7 @@ void nr_schedule_ulsch(module_id_t module_id,
       /* Save information on MCS, TBS etc for the current initial transmission
        * so we have access to it when retransmitting */
       cur_harq->sched_pusch = *sched_pusch;
+      sched_ctrl->sched_ul_bytes += sched_pusch->tb_size;
     } else {
       LOG_D(MAC,
             "%d.%2d UL retransmission RNTI %04x sched %d.%2d HARQ PID %d round %d NDI %d\n",
@@ -929,7 +932,6 @@ void nr_schedule_ulsch(module_id_t module_id,
             cur_harq->ndi);
     }
     UE_info->mac_stats[UE_id].ulsch_current_bytes = sched_pusch->tb_size;
-    sched_ctrl->sched_ul_bytes += sched_pusch->tb_size;
 
     LOG_D(MAC,
           "%4d.%2d RNTI %04x UL sched %4d.%2d start %d RBS %d MCS %d TBS %d HARQ PID %d round %d NDI %d\n",