[PATCH 0/18] powerpc: convert GPR usage to %r0-31 and R0-31

First 5 patches convert us to %r0-31.

Next 12 convert make using R0-31 required in macros.

Last 2 convert instructions where ra = r0 we use 0 rather than the
register value (as suggested by Andreas).

Version 2 adds:
  ra = 0 idea (as Andreas suggested)
  Fixes for 32bit KVM (added ppc44x_defconfig to my testing)
  Based on mpe's next tree which has Antons power7 copy patches which
    needed fixes for this