mm,hwpoison: cleanup unused PageHuge() check

mainline inclusion
from linux-v5.10-rc1
commit 7d9d46ac
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4LE22
CVE: NA

--------------------------------

Drop the PageHuge check, which is dead code since memory_failure() forks
into memory_failure_hugetlb() for hugetlb pages.

memory_failure() and memory_failure_hugetlb() shares some functions like
hwpoison_user_mappings() and identify_page_state(), so they should
properly handle 4kB page, thp, and hugetlb.
Signed-off-by: NNaoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: NOscar Salvador <osalvador@suse.de>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: NMa Wupeng <mawupeng1@huawei.com>
Reviewed-by: Ntong tiangen <tongtiangen@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

mm/memory-failure.c

@@ -1373,10 +1373,7 @@ int memory_failure(unsigned long pfn, int flags)
 	 * page_remove_rmap() in try_to_unmap_one(). So to determine page status
 	 * correctly, we save a copy of the page flags at this time.
 	 */
-	if (PageHuge(p))
-		page_flags = hpage->flags;
-	else
-		page_flags = p->flags;
+	page_flags = p->flags;
 
 	/*
 	 * unpoison always clear PG_hwpoison inside page lock