Do not warn about compatible OpenSSL upgrades

From https://github.com/torproject/tor/pull/951

When releasing OpenSSL patch-level maintenance updates, we do not want to rebuild binaries using it. And since they guarantee ABI stability, we do not have to.

Without this patch, warning messages were produced that confused users: https://bugzilla.opensuse.org/show_bug.cgi?id=1129411