Merge patch series "powerpc: Fix and enforce distinction between immediates and registers"

J. Neuschäfer <j.ne@posteo.net> says:

This patchset changes the definition r0 etc. to %r0, so that the
assembler can check that registers are only used where expected, and
fixes the fallout.

Link: https://lore.kernel.org/r/20241212-gpr-checks-v1-0-8c084c5fc0b6@posteo.net