Follow-up for 1cdbff1c84.
After the commit 1cdbff1c84, each entry .conf contains
redundant slash like the following:
```
$ cat xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-5.9.8-200.fc33.x86_64.conf
title Fedora 33 (Thirty Three)
version 5.9.8-200.fc33.x86_64
machine-id xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
options root=/dev/nvme0n1p2 ro rootflags=subvol=system/fedora selinux=0 audit=0
linux //xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/5.9.8-200.fc33.x86_64/linux
initrd //xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/5.9.8-200.fc33.x86_64/initrd
```
Yu Watanabe
cd0d230e7b