psa: aead: Move key resolution
psa: aead: Move key resolution

As we want to do Mbed TLS aead operations as a
driver does, aead operations should not access
the key slot as key slots are not available to
drivers.

First step in this PR: move key resolution from
aead operation setup to psa_aead_encrypt/decrypt
APIs.

Signed-off-by: Ronald Cron <b35ff5b7ca26c4ae9b66b92f2cf34224c8e26b08@arm.com>

NXPmicro/mbedtls,NXPmicro/mbedtls,ARMmbed/mbedtls,NXPmicro/mbedtls,NXPmicro/mbedtls,Mbed-TLS/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls