Use &raw in the compiler

Like #130865 did for the standard library, we can use `&raw` in the
compiler now that stage0 supports it. Also like the other issue, I did
not make any doc or test changes at this time.

compiler/stable_mir/src/compiler_interface.rs

@@ -255,7 +255,7 @@ where
     if TLV.is_set() {
         Err(Error::from("StableMIR already running"))
     } else {
-        let ptr: *const () = std::ptr::addr_of!(context) as _;
+        let ptr: *const () = (&raw const context) as _;
         TLV.set(&Cell::new(ptr), || Ok(f()))
     }
 }