nilfs2: Remove check for PageError

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>

fs/nilfs2/dir.c

@@ -194,7 +194,7 @@ static struct page *nilfs_get_page(struct inode *dir, unsigned long n)
 	if (!IS_ERR(page)) {
 		kmap(page);
 		if (unlikely(!PageChecked(page))) {
-			if (PageError(page) || !nilfs_check_page(page))
+			if (!nilfs_check_page(page))
 				goto fail;
 		}
 	}