mm: compaction: convert to use a folio in isolate_migratepages_block()

Directly use a folio instead of page_folio() when page successfully
isolated (hugepage and movable page) and after folio_get_nontail_page(),
which removes several calls to compound_head().

Link: https://lkml.kernel.org/r/20230619110718.65679-1-wangkefeng.wang@huawei.com


Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: James Gowans <jgowans@amazon.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>