setup-disk: swapon fails when reinstalling without LVM

Running setup-disk with sys or (crypt and sys) after previously running setup-disk with crypt and lvm and sys results in swap not enabling.

Steps to reproduce:

1. Run setup-disk. Do a crypt lvm sys installation.
2. Run setup-disk. Do a sys installation.

After Creating file systems... swapon -a will fail with the following message:

swapon: UUID=589...: No such file or directory

The installation is continued as normal, but the installed system fails to enable swap on boot with the same error message.

Workaround: Install util-linux before running setup-disk the second time.