Add ObjectManager in the right place

Per
https://gerrit.openbmc.org/c/openbmc/phosphor-dbus-interfaces/+/55308
dbus-sensors has been putting the ObjectManager in the wrong place.  Fix
that.

Tested:
Loaded build with all patches under this same topic, and observed IPMI
and Redfish trees working correctly and responding with sensor data.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Iefe050fe50658de6e1f215eab95b1f772e50eb4a
diff --git a/src/IpmbSensor.cpp b/src/IpmbSensor.cpp
index f594ed5..39e385d 100644
--- a/src/IpmbSensor.cpp
+++ b/src/IpmbSensor.cpp
@@ -601,8 +601,9 @@
 
     boost::asio::io_service io;
     auto systemBus = std::make_shared<sdbusplus::asio::connection>(io);
+    sdbusplus::asio::object_server objectServer(systemBus, true);
+    objectServer.add_manager("/xyz/openbmc_project/sensors");
     systemBus->request_name("xyz.openbmc_project.IpmbSensor");
-    sdbusplus::asio::object_server objectServer(systemBus);
 
     initCmdTimer = std::make_unique<boost::asio::steady_timer>(io);