tests: Replace 'suite' with 'tenv'

Change-Id: I777ec59ffd83b861ddc09e85e52d7a8896264b8c
diff --git a/sysmocom/suites/4g/iperf3_dl.py b/sysmocom/suites/4g/iperf3_dl.py
index 88ae82d..d4fa649 100755
--- a/sysmocom/suites/4g/iperf3_dl.py
+++ b/sysmocom/suites/4g/iperf3_dl.py
@@ -12,10 +12,10 @@
     print_result_node(cli_res, 'client')
     print_result_node(srv_res, 'server')
 
-epc = suite.epc()
-enb = suite.enb()
-ue = suite.modem()
-iperf3srv = suite.iperf3srv({'addr': epc.tun_addr()})
+epc = tenv.epc()
+enb = tenv.enb()
+ue = tenv.modem()
+iperf3srv = tenv.iperf3srv({'addr': epc.tun_addr()})
 iperf3srv.set_run_node(epc.run_node())
 iperf3cli = iperf3srv.create_client()
 iperf3cli.set_run_node(ue.run_node())