autoinstall with storage layout "hybrid+ssd=yes" doesn't boot

[Paolo Gentili]

Provisioning a device with autoinstall ends up in a bootloop with error:

```
Please enter the recovery key for disk /dev/disk/by-partuuid/<uuid>: (press TAB for no echo)
```

The `user-data` file with which this behavior is reproducible is:

```
#cloud-config
autoinstall:
  version: 1
  identity:
    hostname: ai-test
    password: "$6$exDY1mhS4KUYCE/2$zmn9ToZwTKLhCw.b4/b.ZRTIZM30JZ4QrOQ2aOXJ8yk96xpcCof0kxKwuX1kqLG/ygbJ1f8wxED22bTL4F46P0"
    username: ubuntu
  ssh:
    install-server: true
  storage:
    layout:
      name: hybrid
      match:
        ssd: yes
```

Removing `match: ssd: yes` everything works fine.