mbedtls/configs/ext/README.md

Summary
-------

The two files:

* crypto_config_profile_medium.h
* tfm_mbedcrypto_config_profile_medium.h

are copyright The Mbed TLS Contributors, and are distributed under the license normally
used by Mbed TLS: a dual Apache 2.0 or GPLv2-or-later license.

Background
----------

The two files crypto_config_profile_medium.h and tfm_mbedcrypto_config_profile_medium.h
are taken verbatim from the TF-M source code here:

https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git/tree/lib/ext/mbedcrypto/mbedcrypto_config

In TF-M, they are distributed under a 3-Clause BSD license, as noted at the top of the files.

In Mbed TLS, with permission from the TF-M project, they are distributed under a dual [Apache-2.0](https://spdx.org/licenses/Apache-2.0.html) OR [GPL-2.0-or-later](https://spdx.org/licenses/GPL-2.0-or-later.html) license, with copyright assigned to The Mbed TLS Contributors.

We only retain the note at the top of the files because we are taking the files verbatim, for ease of
maintenance.