ubifs: dent: Fix some potential memory leaks while iterating entries

Fix some potential memory leaks in error handling branches while
iterating dent entries. For example, function dbg_check_dir()
forgets to free pdent if it exists.
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Cc: <stable@vger.kernel.org>
Fixes: 1e51764a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@nod.at>

fs/ubifs/debug.c

@@ -1123,6 +1123,7 @@ int dbg_check_dir(struct ubifs_info *c, const struct inode *dir)
 			err = PTR_ERR(dent);
 			if (err == -ENOENT)
 				break;
+			kfree(pdent);
 			return err;
 		}