f2fs: make trace enter and end in pairs for unlink

In the f2fs_unlink we do not add trace end for some
error paths, just add.
Signed-off-by: Lihong Kou <koulihong@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/namei.c

@@ -569,15 +569,17 @@ static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
 
 	trace_f2fs_unlink_enter(dir, dentry);
 
-	if (unlikely(f2fs_cp_error(sbi)))
-		return -EIO;
+	if (unlikely(f2fs_cp_error(sbi))) {
+		err = -EIO;
+		goto fail;
+	}
 
 	err = dquot_initialize(dir);
 	if (err)
-		return err;
+		goto fail;
 	err = dquot_initialize(inode);
 	if (err)
-		return err;
+		goto fail;
 
 	de = f2fs_find_entry(dir, &dentry->d_name, &page);
 	if (!de) {