dbus/dbuspassive: drop no longer used bus reference

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I7aff262c95bea9afa48cfb388082893b1e065010
diff --git a/dbus/dbuspassive.cpp b/dbus/dbuspassive.cpp
index ea47122..a90f5ea 100644
--- a/dbus/dbuspassive.cpp
+++ b/dbus/dbuspassive.cpp
@@ -83,8 +83,8 @@
     const std::string& path,
     const std::shared_ptr<DbusPassiveRedundancy>& redundancy) :
     ReadInterface(),
-    _bus(bus), _signal(bus, getMatch(type, id).c_str(), dbusHandleSignal, this),
-    _id(id), _helper(std::move(helper)), _failed(failed), path(path),
+    _signal(bus, getMatch(type, id).c_str(), dbusHandleSignal, this), _id(id),
+    _helper(std::move(helper)), _failed(failed), path(path),
     redundancy(redundancy)
 
 {