[mbed-tls] VIA padlock support

Hello,

Mbed TLS supports AES acceleration with VIA Padlock (MBEDTLS_PADLOCK_C). We do not have the hardware to test it, so this should be considered strictly community-maintained.

We are making a patch to the AES module which has a small risk of breaking VIA padlock support: https://github.com/Mbed-TLS/mbedtls/pull/5896 . If you are using VIA padlock, please test this change and let us know if something's wrong.

On a related note, we intend to drop the Padlock code in the next major version of Mbed TLS (https://github.com/Mbed-TLS/mbedtls/issues/5903). If you care about this feature, please let us know.

Best regards,