The existing ppc implementation in libco only supports
the ELFv1 ABI on PowerPC 64 and therefore can't be used on
Little Endian systems and Big Endian systems running ELFv2
distros.
This commit introduces a new implementation of the libco
API for ppc64 elfv2. It has been tested with bsnes and higan.
The original ppc implementation is maintained for non-ELFv2
targets.