tsan: fix another crash due to processors

Another stack where we try to free sync objects,
but don't have a processors is:

  //   ResetRange
  //   __interceptor_munmap
  //   __deallocate_stack
  //   start_thread
  //   clone

Again, it is a latent bug that lead to memory leaks.
Also, increase amount of memory we scan in MetaMap::ResetRange.
Without that the test does not fail, as we fail to free
the sync objects on stack.

llvm-svn: 269041