Both Windows and MMAP capable implementations fell back to a
non-MEM_LARGE_PAGES/HugeTLB allocation with the large page implementaion
failed. These can can be freed by the corresponding function.

Prior to this, if we fell back to a conventional memory, than will
results in deallocation using munmap/VirtualFree on a memory allocated
using my_malloc_lock. At worst this could succeed and the
my_malloc_lock looses its memory without knowing about it.