Rollup merge of #105050 - WaffleLapkin:uselessrefign, r=jyn514

Remove useless borrows and derefs

They are nothing more than noise.
<sub>These are not all of them, but my clippy started crashing (stack overflow), so rip :(</sub>

compiler/rustc_hir/src/hir.rs

@@ -2437,7 +2437,7 @@ impl<'hir> Ty<'hir> {
     pub fn peel_refs(&self) -> &Self {
         let mut final_ty = self;
         while let TyKind::Rptr(_, MutTy { ty, .. }) = &final_ty.kind {
-            final_ty = &ty;
+            final_ty = ty;
         }
         final_ty
     }