nilfs2: Remove check for PageError

stable inclusion
from stable-v4.19.319
commit c158e493640ce76e76241f0529cebe19770ba5b2
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAGEKP
CVE: CVE-2024-41034

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c158e493640ce76e76241f0529cebe19770ba5b2



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[ Upstream commit 79ea6556 ]

If read_mapping_page() encounters an error, it returns an errno, not a
page with PageError set, so this test is not needed.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Stable-dep-of: 7373a51e7998 ("nilfs2: fix nilfs_empty_dir() misjudgment and long loop on I/O errors")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zhihao Cheng <chengzhihao@huaweicloud.com>