tls: get crypto_info size from tls_cipher_desc in do_tls_setsockopt_conf

We can simplify do_tls_setsockopt_conf using tls_cipher_desc. Also use
get_cipher_desc's result to check if the cipher_type coming from
userspace is valid.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/e97658eb4c6a5832f8ba20a06c4f36a77763c59e.1692977948.git.sd@queasysnail.net


Signed-off-by: Jakub Kicinski <kuba@kernel.org>