Fix LLVM backend for PowerPC
LLVM backend does not work for PowerPC.
From bug #5131 (closed) davidt says the order of business is:
a) Get unregistered working.
b) Get registered without TABLES_NEXT_TO_CODE.
c) Get TABLES_NEXT_TO_CODE working.
d) Ask David where to go from there.
Actually there is now a guide of sorts here.