Set OPENSSL_NO_ENGINE, remove engine code

Set OPENSSL_NO_ENGINE, remove engine code

ENGINE was special. It's horrible code even by the low standards of this
library. Some ports may now try to use the stubs which will fail, but
the fallout from this should be minimal. Of course there are various
language bindings that expose the ENGINE API. OpenSSL 3 disabling ENGINE
by default will likely help fixing this at some point.

ok jsing