mm: memory-failure: directly use IS_ENABLED(CONFIG_HWPOISON_INJECT)

It's more clear and simple to just use IS_ENABLED(CONFIG_HWPOISON_INJECT)
to check whether or not to enable HWPoison injector module instead of
CONFIG_HWPOISON_INJECT/CONFIG_HWPOISON_INJECT_MODULE.

Link: https://lkml.kernel.org/r/20230313053929.84607-1-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/memory-failure.c

@@ -168,7 +168,7 @@ static bool page_handle_poison(struct page *page, bool hugepage_or_freepage, boo
 	return true;
 }
 
-#if defined(CONFIG_HWPOISON_INJECT) || defined(CONFIG_HWPOISON_INJECT_MODULE)
+#if IS_ENABLED(CONFIG_HWPOISON_INJECT)
 
 u32 hwpoison_filter_enable = 0;
 u32 hwpoison_filter_dev_major = ~0U;