Fix a typo in the simulated OLT adapter that was preventing it from
being enabled.

Change-Id: I25b1406ca8a400e6beccf114d3aa36d467bfa65a
diff --git a/voltha/adapters/simulated_olt/simulated_olt.py b/voltha/adapters/simulated_olt/simulated_olt.py
index 067ab2f..0ab3962 100644
--- a/voltha/adapters/simulated_olt/simulated_olt.py
+++ b/voltha/adapters/simulated_olt/simulated_olt.py
@@ -336,7 +336,7 @@
         yield asleep(0.05)
         try:
             log.info("Setting p")
-            p = PmsConfig(
+            p = PmConfigs(
                 default_freq=150,
                 grouped=False,
                 freq_override=False)