resolving minor bug with reverse computation in dumpi traces

src/models/mpi-trace-replay/conf/modelnet-mpi-test.conf

@@ -3,6 +3,7 @@ LPGROUPS
    MODELNET_GRP
    {
       repetitions="27";
+      modelnet_simplenet="1";
       nw-lp="1";
    }
 }

src/models/mpi-trace-replay/model-net-mpi-wrklds.c

@@ -1165,6 +1165,8 @@ static void get_next_mpi_operation_rc(nw_state* s, tw_bf * bf, nw_message * m, t
 			num_bytes_sent -= m->op.u.send.num_bytes;
 		}
 		break;
+
+		case CODES_WK_IRECV:
 		case CODES_WK_RECV:
 		{
 			codes_exec_mpi_recv_rc(s, m, lp);