Rework how protocol specific ciphers in 80-test_ssl_old.t are picked out

The code to do this incorrectly assumed that the protocol version
could be used as a valid cipher suite  for the 'openssl cipher'
command.  While this is true in some cases, that isn't something to be
trusted.  Replace that assumption with code that takes the full
'openssl ciphers' command output and parses it to find the ciphers we
look for.

Reviewed-by: Emilia Käsper <emilia@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2956)