[s2167] Restore mmap extractor build with CMake by adding preprocessor

Thanks to @Cyberium

(based on commit [12724] - a934f45)
[s2168] Add missing DT_POLIREF64 preprocessor.

Signed-off-by: Cala <calaftp@free.fr>
Merge https://github.com/cmangos/mangos-tbc