docs/vm: rename documentation files to .rst

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7c204e3..5af974a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3289,7 +3289,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
 				 * table protection not changing it to point
 				 * to a new page.
 				 *
-				 * See Documentation/vm/mmu_notifier.txt
+				 * See Documentation/vm/mmu_notifier.rst
 				 */
 				huge_ptep_set_wrprotect(src, addr, src_pte);
 			}
@@ -4355,7 +4355,7 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma,
 	 * No need to call mmu_notifier_invalidate_range() we are downgrading
 	 * page table protection not changing it to point to a new page.
 	 *
-	 * See Documentation/vm/mmu_notifier.txt
+	 * See Documentation/vm/mmu_notifier.rst
 	 */
 	i_mmap_unlock_write(vma->vm_file->f_mapping);
 	mmu_notifier_invalidate_range_end(mm, start, end);