Remove unused Lift derives.

I found these by commenting out all `Lift` derives and then adding back
the ones that were necessary to successfully compile.

compiler/rustc_middle/src/ty/mod.rs

@@ -1510,7 +1510,7 @@ impl<'a, 'tcx> IntoIterator for &'a InstantiatedPredicates<'tcx> {
     }
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable, Lift)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable, TyEncodable, TyDecodable)]
 #[derive(TypeFoldable, TypeVisitable)]
 pub struct OpaqueTypeKey<'tcx> {
     pub def_id: LocalDefId,
@@ -1793,7 +1793,7 @@ impl<'tcx> ParamEnv<'tcx> {
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, TypeFoldable, TypeVisitable)]
-#[derive(HashStable, Lift)]
+#[derive(HashStable)]
 pub struct ParamEnvAnd<'tcx, T> {
     pub param_env: ParamEnv<'tcx>,
     pub value: T,