gh-95095: Use SSL_CTX_get_max_proto_version instead of SSL_CTX_ctrl (GH-95096)

The wrapper macros are more readable and match the form recommended in
the OpenSSL documentation. They also slightly less error-prone, as the
mapping of arguments to SSL_CTX_ctrl is not always clear. (Though in
this case it's straightforward.)
https://www.openssl.org/docs/man1.1.1/man3/SSL_CTX_get_max_proto_version.html
(cherry picked from commit 936f71e5d4f50f2238b0320d44f7fb5f88e39809)

Co-authored-by: David Benjamin <davidben@davidben.net>