We have a special file, tag.h, which serves as a place to store whatever kernel pool allocation tag yet we still have some tags sparse over the kernel code... So just re-group them in one unique place.
RtlGetNtProductType comes into two variants: one in user-mode that is exported for use from NTDLL layer and the kernel-mode that is used exclusively by the NT kernel. The kernel-mode variant of the function is not exported.
which implements the required functionality.
ntdll and ntoskrnl now have a wrapper for this, with SEH.
This protects the function against malformed / bad images,
whilst still being able to use the code in freeldr et al.
Idea from Thomas.
CORE-14857
