mm/page_alloc: remove obsolete comment in zone_statistics()

Since commit 43c95bcc ("mm/page_alloc: reduce duration that IRQs are
disabled for VM counters"), zone_statistics() is not called with
interrupts disabled.  Update the corresponding comment.

Link: https://lkml.kernel.org/r/20220916072257.9639-5-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/page_alloc.c

@@ -3671,8 +3671,6 @@ void __putback_isolated_page(struct page *page, unsigned int order, int mt)
 
 /*
  * Update NUMA hit/miss statistics
- *
- * Must be called with interrupts disabled.
  */
 static inline void zone_statistics(struct zone *preferred_zone, struct zone *z,
 				   long nr_account)