building on amd64 and note, that support for other platforms is easy
too, as long as one has a system to test on.
Redirect a few functions directly to the standard implementations using
defines, instead of using function-wrappers.
This port ought to use a port-installed libtomcrypt instead of building its
own version of same. Unfortunately, our security/libtomcrypt does not
(yet?) install a shared version.
