Revert "Add limit and shrink policy for recycler (#15320)"

This reverts commit c2e8814dce.

perf/src/cuda_runtime.rs

@@ -70,9 +70,6 @@ impl<T: Default + Clone + Sized> Reset for PinnedVec<T> {
     fn set_recycler(&mut self, recycler: Weak<RecyclerX<Self>>) {
         self.recycler = recycler;
     }
-    fn unset_recycler(&mut self) {
-        self.recycler = Weak::default();
-    }
 }
 
 impl<T: Clone + Default + Sized> From<PinnedVec<T>> for Vec<T> {