psa_key_creation_method_t enum

During psa_import_key().

During psa_generate_key().

During psa_key_derivation_output_key().

During psa_copy_key().

A key is being registered with mbedtls_psa_register_se_key(). The core only passes this value to psa_drv_se_key_management_t::p_validate_slot_number, not to psa_drv_se_key_management_t::p_allocate. The call to `p_validate_slot_number` is not followed by any other call to the driver: the key is considered successfully registered if the call to `p_validate_slot_number` succeeds, or if `p_validate_slot_number` is null. With this creation method, the driver must return #PSA_SUCCESS if the given attributes are compatible with the existing key in the slot, and #PSA_ERROR_DOES_NOT_EXIST if the driver can determine that there is no key with the specified slot number. This is an Mbed TLS extension.