Redundant license "libzip" should just be BSD-3-Clause

### Description

Per https://libzip.org/license/, the project is released under the BSD-3-Clause.

The above URL is what I'm redirected to when I click the `homepage_url` portion at https://scancode-licensedb.aboutcode.org/libzip.

I'm using an older scancode-toolkit version, but I see that this license still exists under the latest `develop` branch.
https://github.com/nexB/scancode-toolkit/blob/develop/src/licensedcode/data/licenses/libzip.LICENSE

### How To Reproduce

scancode -l --json-pp output.json libzip.txt --license-text --license-text-diagnostics

[output.json.txt](https://github.com/nexB/scancode-toolkit/files/8911444/output.json.txt)

### System configuration

Running this in Linux using scancode-toolkit 30.1.0 using source download the the `/.configure` script.