Revert "pldm: use std::expected for instance ID allocation"

This reverts commit 70262ed7bf854b25d4b65628bc3c892ddfe9380f.

Change-Id: I1f54d6b60bf3cfa9f00764140eec6167e1e182d6
Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
diff --git a/pldmtool/pldm_cmd_helper.cpp b/pldmtool/pldm_cmd_helper.cpp
index 54260e7..e488557 100644
--- a/pldmtool/pldm_cmd_helper.cpp
+++ b/pldmtool/pldm_cmd_helper.cpp
@@ -89,13 +89,7 @@
 
 void CommandInterface::exec()
 {
-    auto instanceIdResult =
-        pldm::utils::getInstanceId(instanceIdDb.next(mctp_eid));
-    if (!instanceIdResult)
-    {
-        return;
-    }
-    auto instanceId = instanceIdResult.value();
+    instanceId = instanceIdDb.next(mctp_eid);
     auto [rc, requestMsg] = createRequestMsg();
     if (rc != PLDM_SUCCESS)
     {