+universal in apple-gcc42 on ppc

[Joshua Root]

<https://github.com/macports/macports-ports/commit/41e0ae1cf32e0a3d86283818c27e83e06fc8a853> 
seems to be a bit problematic on ppc, see for example:

<https://build.macports.org/builders/ports-10.5_ppc_legacy-builder/builds/16543/steps/install-dependencies/logs/stdio>

I guess on ppc it should probably set 'configure.universal_archs ppc 
ppc64' (if that works) or just not declare a universal variant?

- Josh