Auto merge of #111567 - Urgau:uplift_cast_ref_to_mut, r=b-naber

Uplift `clippy::cast_ref_to_mut` lint

This PR aims at uplifting the `clippy::cast_ref_to_mut` lint into rustc.

## `cast_ref_to_mut`

(deny-by-default)

The `cast_ref_to_mut` lint checks for casts of `&T` to `&mut T` without using interior mutability.

### Example

```rust,compile_fail
fn x(r: &i32) {
    unsafe {
        *(r as *const i32 as *mut i32) += 1;
    }
}
```

### Explanation

Casting `&T` to `&mut T` without interior mutability is undefined behavior, as it's a violation of Rust reference aliasing requirements.

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Mostly followed the instructions for uplifting a clippy lint described here: https://github.com/rust-lang/rust/pull/99696#pullrequestreview-1134072751

`@rustbot` label: +I-lang-nominated
r? compiler

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For Clippy:

changelog: Moves: Uplifted `clippy::cast_ref_to_mut` into rustc

0 files changed, 0 insertions, 0 deletions