Fix more clippy lints.

examples/linux-timerfd.rs

@@ -29,7 +29,7 @@ fn main() -> std::io::Result<()> {
                 // Safety: Assume `as_raw_fd()` returns a valid fd; when `AsFd`
                 // is stabilized, we can remove this unsafe and simplify.
                 let fd = unsafe { BorrowedFd::borrow_raw(t.as_raw_fd()) };
-                rustix::io::read(&fd, &mut [0u8; 8]).map_err(io::Error::from)
+                rustix::io::read(fd, &mut [0u8; 8]).map_err(io::Error::from)
             })
             .await?;
         Ok(())