tests: Replace 'suite' with 'tenv'

Change-Id: I777ec59ffd83b861ddc09e85e52d7a8896264b8c
diff --git a/sysmocom/suites/encryption/register_a5_1_authreq.py b/sysmocom/suites/encryption/register_a5_1_authreq.py
index 077819b..5391f14 100755
--- a/sysmocom/suites/encryption/register_a5_1_authreq.py
+++ b/sysmocom/suites/encryption/register_a5_1_authreq.py
@@ -2,7 +2,7 @@
 from osmo_gsm_tester.testenv import *
 
 import testlib
-suite.test_import_modules_register_for_cleanup(testlib)
+tenv.test_import_modules_register_for_cleanup(testlib)
 from testlib import encryption_test_setup_run
 
 encryption_test_setup_run(True, 'a5_1')