fuzz/server.c: Fix build error on OPENSSL_NO_{DSA,EC,DEPECATED_3_0}
fuzz/server.c: Fix build error on OPENSSL_NO_{DSA,EC,DEPECATED_3_0}

Reviewed-by: Matt Caswell <1fa2ef4755a9226cb9a0a4840bd89b158ac71391@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13110)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl