mm: kfence: use PAGE_ALIGNED helper

Use PAGE_ALIGNED macro instead of IS_ALIGNED and passing PAGE_SIZE.

Link: https://lkml.kernel.org/r/20220520021833.121405-1-wangkefeng.wang@huawei.com


Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>