linux-user/ppc: use the Linux register layout

linux-user/ppc: use the Linux register layout

The dynamic linker converts the Linux layout to the AIX layout and is
reentrant so it won't do it a second time if it's already been
converted. In short it work just fine with either register layout.

OTOH, statically linked binaries expect a Linux layout.

Remove code converting the Linux layout to AIX layout so that all
binaries are presented the Linux Layout.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>