[ELF2] Add a base set of PPC64 relocations

This is mostly an adaptation of the code in LLVM's
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp, and handles a sufficient
number of relocations to link a 'hello world' program on big-Endian PPC64/Linux
(ELF v1 ABI).

llvm-svn: 250101
2 files changed