Rollup merge of rust-lang#114784 - Urgau:many-improve-invalid_reference_casting-lint, r=est31

Improve `invalid_reference_casting` lint

This PR improves the `invalid_reference_casting` lint:
 - by considering an unlimited number of casts instead only const to mut ptr
 - by also considering ptr-to-integer and integer-to-ptr casts
 - by also taking into account [`ptr::cast`](https://doc.rust-lang.org/std/primitive.pointer.html#method.cast), [`ptr::cast`](https://doc.rust-lang.org/std/primitive.pointer.html#method.cast-1) and [`ptr::cast_const`](https://doc.rust-lang.org/std/primitive.pointer.html#method.cast_const)

Most of this improvements comes from skimming Github Code Search result for [`&mut \*.*as \*const`](https://github.com/search?q=lang%3Arust+%2F%26mut+%5C*.*as+%5C*const%2F&type=code)

r? ``@est31`` (maybe)

Author: matthiaskrgr

core/src/ptr/const_ptr.rs

@@ -55,6 +55,7 @@ impl<T: ?Sized> *const T {
     /// Casts to a pointer of another type.
     #[stable(feature = "ptr_cast", since = "1.38.0")]
     #[rustc_const_stable(feature = "const_ptr_cast", since = "1.38.0")]
+    #[rustc_diagnostic_item = "const_ptr_cast"]
     #[inline(always)]
     pub const fn cast<U>(self) -> *const U {
         self as _

core/src/ptr/mut_ptr.rs

@@ -112,6 +112,7 @@ impl<T: ?Sized> *mut T {
     /// [`cast_mut`]: #method.cast_mut
     #[stable(feature = "ptr_const_cast", since = "1.65.0")]
     #[rustc_const_stable(feature = "ptr_const_cast", since = "1.65.0")]
+    #[rustc_diagnostic_item = "ptr_cast_const"]
     #[inline(always)]
     pub const fn cast_const(self) -> *const T {
         self as _