apps/speed.c: skip binary curves when compiling with OPENSSL_NO_EC2M

openssl speed doesn't take into account that the library could be
compiled without the support for the binary curves and happily uses
them, which results in EC_GROUP_new_by_curve_name() errors.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8422)

(cherry picked from commit d61f489b)