Remove `mbedtls_pk_rsassa_pss_options`

### Suggested enhancement

After https://github.com/Mbed-TLS/mbedtls/pull/10130 and https://github.com/Mbed-TLS/TF-PSA-Crypto/pull/253 will be merged there will be no more usage of `mbedtls_pk_rsassa_pss_options` so the structure can be removed.

### Justification

TF-PSA-Crypto needs this because `mbedtls_pk_rsassa_pss_options` will become useless.
