These were all build-pass before and don't seem to need it.

Helps with rust-lang#62277

Tweak `'static` suggestion code

Fix rust-lang#71196.

Remove unused rustc_serialize::hex module

* Remove unused `rustc_serialize::hex` module
* Cleanup `Cargo.toml`

…laumeGomez

Moving all rustdoc-ui tests to check-pass

These were all build-pass before and don't seem to need it.

Helps with rust-lang#62277

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Use assoc int consts3

Define module level int consts with associated constants instead of `min_value()` and `max_value()`. So the code become consistent with what the docs recommend etc. Seems natural.

Also remove the last usages of the int module constants from this repo (except src/test/ directory which I have still not really done anything in). Some places were missed in the previous PRs because the code uses `crate::<IntTy>` to reach the constants.

This is a continuation of rust-lang#70857

r? @dtolnay