Invalid SPDX: PackageLicenseInfoFromFiles: x11vnc-openssl-exception

### Description

ScanCode generates a license name "x11vnc-openssl-exception".
It should be prefixed by "LicenseRef-"

### How To Reproduce

Download ```haproxy-2.0.19.tar.gz``` from ```https://www.haproxy.org/download/2.0/src/haproxy-2.0.19.tar.gz```

```
scancode -c -l -i --license-text --spdx-tv haproxy-2.0.19.spdx haproxy-2.0.19
```

Result:
[haproxy-2.0.19.spdx.txt](https://github.com/nexB/scancode-toolkit/files/10723941/haproxy-2.0.19.spdx.txt)

### System configuration

```
./scancode --version
ScanCode version: 32.0.0rc1
ScanCode Output Format version: 3.0.0
SPDX License list version: 3.19
```

Ubuntu 22.10