MEDIUM: ssl: implement rsa/ecdsa selection with WolfSSL

MEDIUM: ssl: implement rsa/ecdsa selection with WolfSSL

PR https://github.com/wolfSSL/wolfssl/pull/6963 implements primitives to
extract ciphers and algorithm signatures.

It allows to chose a certificate depending on the sigals and
ciphers presented by the client (RSA or ECDSA).

Since WolfSSL does not implement the clienthello callback, the patch
uses the certificate callback (SSL_CTX_set_cert_cb())

The callback is inspired by our clienthello callback, however the
extraction of client ciphers and sigalgs is simpler,
wolfSSL_get_sigalg_info() and wolfSSL_get_ciphersuite_info() are used.

This is not enabled by default yet as the PR was not merged.