Rollup merge of #101423 - mkroening:hermit-warnings, r=sanxiyn

Fix hermit warnings

This fixes two `unused_imprt` and one `dead_code` warning for hermit.

library/std/src/sys/hermit/mutex.rs

@@ -2,7 +2,6 @@ use crate::cell::UnsafeCell;
 use crate::collections::VecDeque;
 use crate::hint;
 use crate::ops::{Deref, DerefMut, Drop};
-use crate::ptr;
 use crate::sync::atomic::{AtomicUsize, Ordering};
 use crate::sys::hermit::abi;
 

library/std/src/sys/hermit/net.rs

@@ -487,6 +487,4 @@ pub mod netc {
 
     #[derive(Copy, Clone)]
     pub struct sockaddr {}
-
-    pub type socklen_t = usize;
 }

library/std/src/sys/hermit/rwlock.rs

@@ -1,6 +1,5 @@
 use crate::cell::UnsafeCell;
 use crate::sys::locks::{MovableCondvar, Mutex};
-use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 
 pub struct RwLock {
     lock: Mutex,