tls: use tls_cipher_desc to simplify do_tls_getsockopt_conf

tls: use tls_cipher_desc to simplify do_tls_getsockopt_conf

Every cipher uses the same code to update its crypto_info struct based
on the values contained in the cctx, with only the struct type and
size/offset changing. We can get those  from tls_cipher_desc, and use
a single pair of memcpy and final copy_to_user.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/c21a904b91e972bdbbf9d1c6d2731ccfa1eedf72.1692977948.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>