Warning about missing docs (in private items)

[scullionw]

same as https://github.com/LukasKalbertodt/confique/issues/25

but for #![deny(clippy::missing_docs_in_private_items)]

To reproduce:

1. Have a config struct that the lib does not make public
2. Use #![deny(clippy::missing_docs_in_private_items)]

Seems like the doc comment is not passed through in this case?

[LukasKalbertodt]

And I assume you can't simply annotate your struct with #[allow(clippy::missing_docs_in_private_items)]?

So this crate would have to add said attribute to some items. Now I wonder:

• Is it ok to just add the attribute even if I don't use clippy at all?
• Clippy could always add new lints that I don't know about. No point in adding hundreds of individual attributes to silence every lint individually. Shouldn't clippy just ignore generated code? Or should this crate just add #[allow(warnings)] to generated code? :thinking: