make clippy happy

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/lxcseccomp.rs

@@ -399,15 +399,15 @@ impl ProxyMessageBuffer {
     pub fn arg_fd(&self, arg: u32, flags: c_int) -> Result<Fd, Error> {
         let fd = self.arg(arg)? as RawFd;
         // we pass negative ones 'as-is', others get opened via the pidfd
-        if fd == libc::AT_FDCWD {
+        Ok(if fd == libc::AT_FDCWD {
             // NOTE: we could pass this one through, but let's be explicit here, in the future we
             // might want to reuse this one?
-            Ok(self.pid_fd().fd_cwd()?)
+            self.pid_fd().fd_cwd()?
         } else if fd < 0 {
-            return Ok(Fd(fd));
+            Fd(fd)
         } else {
-            Ok(self.pid_fd().fd_num(fd, flags)?)
-        }
+            self.pid_fd().fd_num(fd, flags)?
+        })
     }
 
     /// Checked way to get a c_uint argument.