remove useless parentheses + clippy fixes

apps/src/cmsg.rs

@@ -72,7 +72,7 @@ impl<'a> Encoder<'a> {
         let space =
             unsafe { libc::CMSG_SPACE(mem::size_of_val(&value) as _) as usize };
         assert!(
-            self.hdr.msg_controllen as usize >= self.len + space,
+            self.hdr.msg_controllen >= self.len + space,
             "control message buffer too small"
         );
         let cmsg = self.cmsg.take().expect("no control buffer space remaining");
@@ -107,7 +107,7 @@ impl<'a> Drop for Encoder<'a> {
 pub unsafe fn decode<T: Copy>(cmsg: &libc::cmsghdr) -> T {
     assert!(mem::align_of::<T>() <= mem::align_of::<libc::cmsghdr>());
     debug_assert_eq!(
-        cmsg.cmsg_len as usize,
+        cmsg.cmsg_len,
         libc::CMSG_LEN(mem::size_of::<T>() as _) as usize
     );
     ptr::read(libc::CMSG_DATA(cmsg) as *const T)

apps/src/recvfrom.rs

@@ -84,7 +84,7 @@ fn recvmsg(
     let mut iov = IoSliceMut::new(buf);
     let mut name = MaybeUninit::<libc::sockaddr_storage>::uninit();
     let mut ctrl = cmsg::Aligned(MaybeUninit::<
-        [u8; (std::mem::size_of::<libc::in6_pktinfo>() as _)],
+        [u8; std::mem::size_of::<libc::in6_pktinfo>() as _],
     >::uninit());
     let mut hdr = unsafe { std::mem::zeroed::<libc::msghdr>() };