mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()

Commit b239f7da ("percpu: set PCPU_BITMAP_BLOCK_SIZE to PAGE_SIZE")
removed the parameter 'for_alloc', so remove this comment.

Link: https://lkml.kernel.org/r/1630576043-21367-1-git-send-email-jingxiangfeng@huawei.comSigned-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/percpu.c

@@ -1520,9 +1520,6 @@ static void pcpu_free_chunk(struct pcpu_chunk *chunk)
  * Pages in [@page_start,@page_end) have been populated to @chunk.  Update
  * the bookkeeping information accordingly.  Must be called after each
  * successful population.
- *
- * If this is @for_alloc, do not increment pcpu_nr_empty_pop_pages because it
- * is to serve an allocation in that area.
  */
 static void pcpu_chunk_populated(struct pcpu_chunk *chunk, int page_start,
 				 int page_end)