Fix partition to filesystem.

[JensKuehnel]

Proposed change

Type of change

• [ ] Document existing features within Home Assistant
• [ ] Document new or changing features which there is an existing pull request elsewhere
• [X] Spelling or grammatical corrections, or rewording for improved clarity
• [ ] Changes to the backend of this documentation
• [ ] Removed stale or deprecated documentation

Additional information

• This PR fixes or closes issue: fixes #
• Link to relevant existing code or pull request:

[frenck]

Use a USB drive with a filesystem (sometime called partition) named

This seems like an incorrect change, the partition has a filesystem, but they are not synonyms.

../Frenck