Fix builds that specify both no-dh and no-ec

Fix builds that specify both no-dh and no-ec

Various sections of code assumed that at least one of dh or ec would be
available. We also now also need to handle cases where a provider has
a key exchange algorithm and TLS-GROUP that we don't know about.

Fixes #13536

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/13549)