Fix missing PLDM transport configuration

The PLDM transport option wasn't actually used. In addition,
throttle the PLDM open failure trace.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Change-Id: I6c5f9151b3230171a1f050d54bbb143334577ab2
diff --git a/pldm.cpp b/pldm.cpp
index 67c8cc4..3703a02 100644
--- a/pldm.cpp
+++ b/pldm.cpp
@@ -709,8 +709,11 @@
     auto rc = pldmOpen();
     if (rc)
     {
-        log<level::ERR>(
-            std::format("sendPldm: pldmOpen failed rc={}", rc).c_str());
+        if (!throttleTraces)
+        {
+            log<level::ERR>(
+                std::format("sendPldm: pldmOpen failed rc={}", rc).c_str());
+        }
         freePldmInstanceId();
         return;
     }