__page_handle_poison() returns bool that shows whether
take_page_off_buddy() has passed or not now.  But we will want to
distinguish another case of "dissolve has passed but taking off failed" by
its return value.  So change the type of the return value.  No functional
change.

Link: https://lkml.kernel.org/r/20220714042420.1847125-7-naoya.horiguchi@linux.devSigned-off-by: NNaoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: NMiaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>