Remove __unmap_hugepage_range() from the header file, because it is only
used in hugetlb.c.

Link: https://lkml.kernel.org/r/20210917165108.9341-1-peterx@redhat.comSigned-off-by: NPeter Xu <peterx@redhat.com>
Suggested-by: NMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: NJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: NMuchun Song <songmuchun@bytedance.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>