Making zero-assembler the default on ppc

[Gary Benson]

Hi all,

Does anyone mind if I make the zero-assembler port the default on ppc?
I'd like to add a configure option to allow zero to be built on any
platform, but having ppc-specific stuff in the hotspot makefiles is
making this a pain.  The main impact of this change from a packaging 
point of view is that libffi will become mandatory on ppc and ppc64.

Cheers,
Gary

PS twisti this will not affect you