8548 CPU is GCC's name for the e500v2, so accept this in clang. The
e500v2 doesn't support lwsync, so define NO_LWSYNC for this as well,
as GCC does.
Yeah, I noticed that after I committed it. Problem is, to submit that for review, I need a valid reduced test case., and my laziness/busy-ness has prevented me from creating a reduced test case in LLVM language.