We call this "zig-build" instead of just "zig" as this build-style
relies on usage of the zig build system. In the future, other build
systems such as meson may support zig code. Furthermore, the zig
build system may be used to build C/C++ code as well, not just zig.
for now, these profiles set -mcpu to power8 and -mtune to power9
to match our ppc64le profiles, since there isn't really any native
harwdare to run these on (at least yet), and any packages will be
experimental for now anyway
