PVS-Studio warning V640 for DDKSamples

#define MP_FREE_MEMORY(_Memory) \
  MpFreeMemory(_Memory); _Memory = NULL;

NDIS_STATUS
StaStartScan(....)
{
  ....
  if (pExternalScanRequest != NULL)
    MP_FREE_MEMORY(pExternalScanRequest);
  ....
}

This suspicious code was found in DDKSamples project by PVS-Studio static code analyzer.
Warning message is:
V640 The code's operational logic does not correspond with its formatting. The second statement will always be executed. It is possible that curly brackets are missing. st_scan.c 564

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/