[Hugetlb x86] Small hugetlb arch updates for i386 and x86_64

Hi Andrew. The following 3 patches update the i386 and x86_64 hugetlb arch code to bring it closer to the other architectures. The first patch adds a pte_huge() macro. The second patch moves the "stale pte" check into huge_pte_alloc() which seems more appropriate to me. The third patch checks

[Hugetlb x86] Small hugetlb arch updates for i386 and x86_64

Hi Andrew. The following 3 patches update the i386 and x86_64 hugetlb arch code to bring it closer to the other architectures. The first patch adds a pte_huge() macro. The second patch moves the stale pte check into huge_pte_alloc() which seems more appropriate to me. The third patch checks