Limit the output of the enc -ciphers command

to just the ciphers enc can
process.  This means no AEAD ciphers and no XTS mode.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2876)
(cherry picked from commit 777f1708)