pldmtool: use correct recordChangeNumber in pdr transmission

The recordChangeNumber comes from the first part of the pdr
transmission, and should be reused during the multipart transmission.

Middle parts of a multipart transmission do not have the header
included, so trying to obtain the record change number from them is
wrong.

Change-Id: Ie7d60aa6758f9d1a9450ecda8af35a83090fb5dd
Signed-off-by: Roger G. Coscojuela <roger.gili-coscojuela@sipearl.com>
diff --git a/pldmtool/pldm_platform_cmd.cpp b/pldmtool/pldm_platform_cmd.cpp
index 62a9d3a..7fd011e 100644
--- a/pldmtool/pldm_platform_cmd.cpp
+++ b/pldmtool/pldm_platform_cmd.cpp
@@ -355,7 +355,7 @@
             {
                 nextPartRequired = true;
                 dataTransferHandle = nextDataTransferHndl;
-                struct pldm_pdr_hdr* pdr_hdr = new (respRecordData)
+                struct pldm_pdr_hdr* pdr_hdr = new (recordData.data())
                     pldm_pdr_hdr;
                 recordChangeNumber = pdr_hdr->record_change_num;
                 operationFlag = PLDM_GET_NEXTPART;