sensors: don't pass excess conn handler

We don't need to pass connection handler to setInitialProperties method
since it already part of the sensor class.

Tested: no changes in behaviour.
Signed-off-by: Andrei Kartashev <a.kartashev@yadro.com>
Change-Id: Icaaccbeaf14e22648a6a1bce381f0f0a606b0ddd
diff --git a/src/PSUSensor.cpp b/src/PSUSensor.cpp
index c405ef5..99845b5 100644
--- a/src/PSUSensor.cpp
+++ b/src/PSUSensor.cpp
@@ -90,11 +90,11 @@
     // register and initialize "Associations" property.
     if (label.empty() || tSize == thresholds.size())
     {
-        setInitialProperties(conn, sensorUnits);
+        setInitialProperties(sensorUnits);
     }
     else
     {
-        setInitialProperties(conn, sensorUnits, label, tSize);
+        setInitialProperties(sensorUnits, label, tSize);
     }
 
     association = objectServer.add_interface(dbusPath, association::interface);