objcrypt-fox fails to cross build from source, because it passes host
compiler flags to the build compiler. As a result, cross builds for
amd64 and arm64 fail. The relevant invocation is actually hidden from
the verbose build log. It happens via MAKEDEPEND where "gcc" is hard
coded. I'm attaching a patch to also make this substitutable. Please
consider applying it and forwarding it upstream.

Helmut