mm/hwpoison: fix some obsolete comments

Since commit cb731d6c ("vmscan: per memory cgroup slab shrinkers"),
shrink_node_slabs is renamed to drop_slab_node.  And doit argument is
changed to forcekill since commit 6751ed65 ("x86/mce: Fix
siginfo_t->si_addr value for non-recoverable memory faults").

Link: https://lkml.kernel.org/r/20210814105131.48814-5-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memory-failure.c

@@ -296,7 +296,7 @@ void shake_page(struct page *p, int access)
 	}
 
 	/*
-	 * Only call shrink_node_slabs here (which would also shrink
+	 * Only call drop_slab_node here (which would also shrink
 	 * other caches) if access is not potentially fatal.
 	 */
 	if (access)
@@ -391,8 +391,8 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
 /*
  * Kill the processes that have been collected earlier.
  *
- * Only do anything when DOIT is set, otherwise just free the list
- * (this is used for clean pages which do not need killing)
+ * Only do anything when FORCEKILL is set, otherwise just free the
+ * list (this is used for clean pages which do not need killing)
  * Also when FAIL is set do a force kill because something went
  * wrong earlier.
  */