RFC: Removing PPC_ABI_POWEROPEN

[Ralf Corsepius]

Hi again,

Another step towards simplicity of the powerpc port:

I would want to remove PPC_ABI_POWEROPEN, i.e. to abandon the PowerOpen-
ABI. AFAICT, it is not used anywhere inside of the source tree and not
supported by any actively maintained RTEMS toolchain.

To me keeping it doesn't make much sense.

Any objections?

If yes, please speak up NOW! 

The patches are reading, committing them to CVS is only a couple of
"return"s away. ;-)

Ralf