Auto merge of #117758 - Urgau:lint_pointer_trait_comparisons, r=davidtwco

Add lint against ambiguous wide pointer comparisons

This PR is the resolution of rust-lang/rust#106447 decided in rust-lang/rust#117717 by T-lang.

## `ambiguous_wide_pointer_comparisons`

*warn-by-default*

The `ambiguous_wide_pointer_comparisons` lint checks comparison of `*const/*mut ?Sized` as the operands.

### Example

```rust
let ab = (A, B);
let a = &ab.0 as *const dyn T;
let b = &ab.1 as *const dyn T;

let _ = a == b;
```

### Explanation

The comparison includes metadata which may not be expected.

-------

This PR also drops `clippy::vtable_address_comparisons` which is superseded by this one.

~~One thing: is the current naming right? `invalid` seems a bit too much.~~

Fixes rust-lang/rust#117717

Author: bors

tests/pass/pointers.rs

@@ -2,6 +2,7 @@
 //@[tree]compile-flags: -Zmiri-tree-borrows
 //@compile-flags: -Zmiri-permissive-provenance
 #![feature(ptr_metadata, const_raw_ptr_comparison)]
+#![allow(ambiguous_wide_pointer_comparisons)]
 
 use std::mem::{self, transmute};
 use std::ptr;

tests/pass/rc.rs

@@ -3,6 +3,7 @@
 //@compile-flags: -Zmiri-strict-provenance
 #![feature(new_uninit)]
 #![feature(get_mut_unchecked)]
+#![allow(ambiguous_wide_pointer_comparisons)]
 
 use std::cell::{Cell, RefCell};
 use std::fmt::Debug;