mm/memory-failure: use zone_pcp_disable() for poison handling

__page_handle_poison() used drain_all_pages() instead of
zone_pcp_disable() because dissolve_free_hugetlb_folio() could restore HVO
vmemmap pages and decrement hugetlb_optimize_vmemmap_key.  That static key
update took cpu_hotplug_lock through static_key_slow_dec(), while
zone_pcp_disable() holds pcp_batch_high_lock.  CPU hotplug takes the locks
in the opposite order through page_alloc_cpu_online/dead(), so the
combination could deadlock.

That dependency no longer exists.  Commit da3e2d1ca43d ("mm/hugetlb:
remove hugetlb_optimize_vmemmap_key static key") removed the HVO static
key and the static_branch_dec() from hugetlb_vmemmap_restore_folio().  The
dissolve_free_hugetlb_folio() path no longer reaches
static_key_slow_dec().

Use zone_pcp_disable() again while dissolving the hugetlb folio and taking
the target page off the buddy allocator.  This prevents the drained PCP
lists from being refilled before take_page_off_buddy() runs, making the
page isolation deterministic.

Link: https://lore.kernel.org/20260514085754.84097-1-kaitao.cheng@linux.dev
Signed-off-by: Kaitao Cheng <chengkaitao@kylinos.cn>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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