host-bmc: host_pdr_handler: Remove unused fields

```
../host-bmc/host_pdr_handler.hpp:277:9: error: private field 'mctp_fd' is not used [-Werror,-Wunused-private-field]
  277 |     int mctp_fd;
      |         ^
../host-bmc/host_pdr_handler.hpp:292:35: error: private field 'bmcEntityTree' is not used [-Werror,-Wunused-private-field]
  292 |     pldm_entity_association_tree* bmcEntityTree;
      |                                   ^
```

Change-Id: I62a948dff51b184bf44f1053b48d3b512e3e2b72
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>
diff --git a/host-bmc/host_pdr_handler.cpp b/host-bmc/host_pdr_handler.cpp
index 61167ab..3621f92 100644
--- a/host-bmc/host_pdr_handler.cpp
+++ b/host-bmc/host_pdr_handler.cpp
@@ -84,15 +84,15 @@
 }
 
 HostPDRHandler::HostPDRHandler(
-    int mctp_fd, uint8_t mctp_eid, sdeventplus::Event& event, pldm_pdr* repo,
-    const std::string& eventsJsonsDir, pldm_entity_association_tree* entityTree,
+    int /* mctp_fd */, uint8_t mctp_eid, sdeventplus::Event& event,
+    pldm_pdr* repo, const std::string& eventsJsonsDir,
+    pldm_entity_association_tree* entityTree,
     pldm_entity_association_tree* bmcEntityTree,
     pldm::InstanceIdDb& instanceIdDb,
     pldm::requester::Handler<pldm::requester::Request>* handler) :
-    mctp_fd(mctp_fd),
-    mctp_eid(mctp_eid), event(event), repo(repo),
-    stateSensorHandler(eventsJsonsDir), entityTree(entityTree),
-    bmcEntityTree(bmcEntityTree), instanceIdDb(instanceIdDb), handler(handler),
+    mctp_eid(mctp_eid),
+    event(event), repo(repo), stateSensorHandler(eventsJsonsDir),
+    entityTree(entityTree), instanceIdDb(instanceIdDb), handler(handler),
     entityMaps(parseEntityMap(ENTITY_MAP_JSON)), oemUtilsHandler(nullptr)
 {
     mergedHostParents = false;