fix: mm: compaction: fix the migration stats in trace_mm_compaction_migratepages...

fix: mm: compaction: fix the migration stats in trace_mm_compaction_migratepages() (v5.17)

See upstream commit :

  commit 84b328aa81216e08804d8875d63f26bda1298788
  Author: Baolin Wang <baolin.wang@linux.alibaba.com>
  Date:   Fri Jan 14 14:08:40 2022 -0800

    mm: compaction: fix the migration stats in trace_mm_compaction_migratepages()

    Now the migrate_pages() has changed to return the number of {normal
    page, THP, hugetlb} instead, thus we should not use the return value to
    calculate the number of pages migrated successfully.  Instead we can
    just use the 'nr_succeeded' which indicates the number of normal pages
    migrated successfully to calculate the non-migrated pages in
    trace_mm_compaction_migratepages().

Link: https://lkml.kernel.org/r/b4225251c4bec068dcd90d275ab7de88a39e2bd7.1636275127.git.baolin.wang@linux.alibaba.com
Change-Id: Ib8e8f2a16a273f16cd73fe63afbbfc25c0a2540c
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>