From: David Gibson <david@gibson.dropbear.id.au>

The PPC64 version of is_aligned_hugepage_range() is buggy.  It is supposed to
test not only that the given range is hugepage aligned, but that it lies
within the address space allowed for hugepages.  We were checking only that
the given range intersected the hugepage range, not that it lay entirely
within it.  This patch fixes the problem and changes the name of some macros
to make it less likely to make that misunderstanding again.