- no longer using home-grown linker - simply compiling and linking switchback.c with test_xxx.c
- updated to handle ppc64 (along with it's weirdo function descriptors...)
- have to be careful not to use exported functions from libvex_arch_linux.a, hence vex_printf -> vexxx_printf in test_xxx.c
git-svn-id: svn://svn.valgrind.org/vex/trunk@1490