Fix redundant import of FromIterator

This is a new lint introduced in rustc.

Author: Amanieu

src/map.rs

@@ -5,7 +5,7 @@ use crate::{Equivalent, TryReserveError};
 use core::borrow::Borrow;
 use core::fmt::{self, Debug};
 use core::hash::{BuildHasher, Hash};
-use core::iter::{FromIterator, FusedIterator};
+use core::iter::FusedIterator;
 use core::marker::PhantomData;
 use core::mem;
 use core::ops::Index;

src/set.rs

@@ -4,7 +4,7 @@ use crate::{Equivalent, TryReserveError};
 use alloc::borrow::ToOwned;
 use core::fmt;
 use core::hash::{BuildHasher, Hash};
-use core::iter::{Chain, FromIterator, FusedIterator};
+use core::iter::{Chain, FusedIterator};
 use core::ops::{BitAnd, BitOr, BitXor, Sub};
 
 use super::map::{self, DefaultHashBuilder, HashMap, Keys};