Correctly label symbols in `n_CLASS_STATIC_ACCESS`
Correctly label symbols in `n_CLASS_STATIC_ACCESS`

Summary: Fixes T6847. These symbols should always be classes, not interfaces.

Test Plan:
```lang=php, name=test.php
<?php

Foo::bar();
```

```lang=bash
> ./scripts/phutil_symbols.php test.php

```

Reviewers: epriestley, #blessed_reviewers

Subscribers: Korvin, epriestley

Maniphest Tasks: T6847

Differential Revision: https://secure.phabricator.com/D11137

julkiewicz/libphutil,julkiewicz/libphutil,julkiewicz/libphutil