Require the OpenSSL 1.1 APIs when compiling ldns

Moving the APIs from OpenSSL 1.1 supporting APIs to 3.x supporting APIs
is a non-trivial effort. Require 1.1 API compatibility to unblock
updating OpenSSL in base to 3.x.

This mirrors what upstream has done in their configure.ac file.

Submitted by: Pierre Pronchery <pierre@freebsdfoundation.org>
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40082