Rationalise copyright notices

Author: thejpster

arm-targets/README.md

@@ -34,7 +34,8 @@ compile with older versions but that may change in any new patch release.
 
 ## Licence
 
-Copyright (c) Ferrous Systems, 2025
+* Copyright (c) Ferrous Systems
+* Copyright (c) The Rust Embedded Devices Working Group developers
 
 Licensed under either [MIT](./LICENSE-MIT) or [Apache-2.0](./LICENSE-APACHE) at
 your option.

cortex-ar/README.md

@@ -27,7 +27,8 @@ compile with older versions but that may change in any new patch release.
 
 ## Licence
 
-Copyright (c) Ferrous Systems, 2025
+* Copyright (c) Ferrous Systems
+* Copyright (c) The Rust Embedded Devices Working Group developers
 
 Licensed under either [MIT](./LICENSE-MIT) or [Apache-2.0](./LICENSE-APACHE) at
 your option.

cortex-r-rt/README.md

@@ -7,7 +7,8 @@ compile with older versions but that may change in any new patch release.
 
 ## Licence
 
-Copyright (c) Ferrous Systems, 2025
+* Copyright (c) Ferrous Systems
+* Copyright (c) The Rust Embedded Devices Working Group developers
 
 Licensed under either [MIT](./LICENSE-MIT) or [Apache-2.0](./LICENSE-APACHE) at
 your option.