Add Item Iface to Track Fan Presence

Item iface has a present bit that phosphor-fan-presence
uses to track presence. Algin to this so we can add it
to redfish.

Tested: Pulled fan and correct bit changed to false

Change-Id: I5bfb5d97b8ad7a4d582b3e41b0f14007cdd88b51
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/include/TachSensor.hpp b/include/TachSensor.hpp
index 2ef1298..c6f255f 100644
--- a/include/TachSensor.hpp
+++ b/include/TachSensor.hpp
@@ -62,6 +62,7 @@
     sdbusplus::asio::object_server& objServer;
     std::shared_ptr<RedundancySensor> redundancy;
     std::unique_ptr<PresenceSensor> presence;
+    std::shared_ptr<sdbusplus::asio::dbus_interface> itemIface;
     boost::asio::posix::stream_descriptor inputDev;
     boost::asio::deadline_timer waitTimer;
     boost::asio::streambuf readBuf;