memory-failure: change type of action_result's param 3 to enum

Change type of action_result's param 3 to enum for type consistency,
and rename mf_outcome to mf_result for clearly.

Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Chen Gong <gong.chen@linux.intel.com>
Cc: Jim Davis <jim.epost@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/mm.h

@@ -2157,7 +2157,7 @@ extern int soft_offline_page(struct page *page, int flags);
 /*
  * Error handlers for various types of pages.
  */
-enum mf_outcome {
+enum mf_result {
 	MF_IGNORED,	/* Error: cannot be handled */
 	MF_FAILED,	/* Error: handling failed */
 	MF_DELAYED,	/* Will be handled later */