Update kernel/src/hil/symmetric_encryption.rs

Co-authored-by: Tyler Potyondy <77175673+tyler-potyondy@users.noreply.github.com>

Author: theonlytruealex

kernel/src/hil/symmetric_encryption.rs

@@ -1,7 +1,6 @@
 // Licensed under the Apache License, Version 2.0 or the MIT License.
 // SPDX-License-Identifier: Apache-2.0 OR MIT
 // Copyright Tock Contributors 2022.
-// Copyright OxidOS Automotive 2026.
 
 //! Interface for symmetric-cipher encryption
 //!