Rollup merge of #87527 - LeSeulArtichaut:no-mir-unsafeck, r=oli-obk

Don't run MIR unsafeck at all when using `-Zthir-unsafeck`

I don't know how I missed this :D
r? ``@oli-obk``

compiler/rustc_mir/src/transform/mod.rs

@@ -259,11 +259,13 @@ fn mir_const<'tcx>(
     }
 
     // Unsafety check uses the raw mir, so make sure it is run.
+    if !tcx.sess.opts.debugging_opts.thir_unsafeck {
         if let Some(param_did) = def.const_param_did {
             tcx.ensure().unsafety_check_result_for_const_arg((def.did, param_did));
         } else {
             tcx.ensure().unsafety_check_result(def.did);
         }
+    }
 
     let mut body = tcx.mir_built(def).steal();