Changeset a3f5b6b in rtems for c/src/exec/score/cpu/powerpc/shared/ppc.h

Added a special CPU model of "rtems_multilib". This is the beginnings
of an experiment to determine what it will take to multilib most of
RTEMS per GNU multilib conventions. It is thought that only
interrupt processing and IO are not multlib-able. This means that
a BSP Kit should include IRQ processing from score/cpu, all peripheral
support (header files from score/cpu, libchip, and libcpu), and the
BSPs themselves. The rest of RTEMS should be multlib-able. But to do
this, all RTEMS CPU model feature flags must be derivable from gcc
cpp predefines. By configuring the bare bsp with the rtems_multilib
CPU model, you can try any combination of CPU CFLAGS and see well how the
logic in that section of the <CPU>.h works. Once all CPU multilib
variations can be built, then RTEMS proper can be multilib'ed and
separated from the BSPs.