mm: remove stale comment __folio_mark_dirty

The __folio_mark_dirty will not mark inode dirty any longer.  Remove the
stale comment of it.

Link: https://lkml.kernel.org/r/20240425131724.36778-5-shikemeng@huaweicloud.comSigned-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Howard Cochran <hcochran@kernelspring.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/page-writeback.c

@@ -2721,8 +2721,7 @@ void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb)
 }
 
 /*
- * Mark the folio dirty, and set it dirty in the page cache, and mark
- * the inode dirty.
+ * Mark the folio dirty, and set it dirty in the page cache.
  *
  * If warn is true, then emit a warning if the folio is not uptodate and has
  * not been truncated.