nilfs2: remove duplicate 'unlikely()' usage

Nested unlikely() calls, IS_ERR already uses unlikely() internally

Link: https://lkml.kernel.org/r/20240904101618.17716-1-konishi.ryusuke@gmail.comSigned-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/nilfs2/page.c

@@ -262,7 +262,7 @@ int nilfs_copy_dirty_pages(struct address_space *dmap,
 			NILFS_FOLIO_BUG(folio, "inconsistent dirty state");
 
 		dfolio = filemap_grab_folio(dmap, folio->index);
-		if (unlikely(IS_ERR(dfolio))) {
+		if (IS_ERR(dfolio)) {
 			/* No empty page is added to the page cache */
 			folio_unlock(folio);
 			err = PTR_ERR(dfolio);