ANDROID: mm: disable speculative page faults for CONFIG_NUMA

NUMA support with speculative page faults might be broken if
vma_replace_policy() replaces the mempolicy object used in
do_anonymous_page()
 alloc_zeroed_user_highpage_movable()
  alloc_page_vma()
    alloc_pages_vma()
      get_vma_policy()
__get_vma_policy() in speculative path does not always refcounts the
mempolicy object, therefore can't be relied on stabilizing it.
Rather than fixing this, just disable speculation for CONFIG_NUMA
for now and fix it if it's ever needed in Android.

Bug: 257443051
Change-Id: Ib5750b9809979a69a42ebfa6c130e123f416f1aa
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Lee Jones <joneslee@google.com>