mm/hugetlb.c: use huge_pte_lock instead of opencoding the lock

No functional change by this patch.

Link: http://lkml.kernel.org/r/20161018090234.22574-1-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb.c

@@ -3713,8 +3713,7 @@ retry:
 		vma_end_reservation(h, vma, address);
 	}
 
-	ptl = huge_pte_lockptr(h, mm, ptep);
-	spin_lock(ptl);
+	ptl = huge_pte_lock(h, mm, ptep);
 	size = i_size_read(mapping->host) >> huge_page_shift(h);
 	if (idx >= size)
 		goto backout;
@@ -4332,8 +4331,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud)
 	if (!spte)
 		goto out;
 
-	ptl = huge_pte_lockptr(hstate_vma(vma), mm, spte);
-	spin_lock(ptl);
+	ptl = huge_pte_lock(hstate_vma(vma), mm, spte);
 	if (pud_none(*pud)) {
 		pud_populate(mm, pud,
 				(pmd_t *)((unsigned long)spte & PAGE_MASK));