um: Remove ppc cruft

That code is a relict from the early days of UML.
ppc support was never completed nor worked.
Let's rip it out.

Signed-off-by: Richard Weinberger <richard@nod.at>

diff --cc arch/um/Makefile-ppc
Simple merge

diff --cc arch/um/sys-ppc/Makefile
Simple merge

diff --cc arch/um/sys-ppc/asm/archparam.h
Simple merge

diff --cc arch/um/sys-ppc/asm/elf.h
Simple merge

diff --cc arch/um/sys-ppc/asm/processor.h
Simple merge

diff --cc arch/um/sys-ppc/misc.S
Simple merge

diff --cc arch/um/sys-ppc/miscthings.c
Simple merge

diff --cc arch/um/sys-ppc/ptrace.c
Simple merge

diff --cc arch/um/sys-ppc/ptrace_user.c
Simple merge

diff --cc arch/um/sys-ppc/shared/sysdep/ptrace.h
Simple merge

diff --cc arch/um/sys-ppc/shared/sysdep/sigcontext.h
Simple merge

diff --cc arch/um/sys-ppc/shared/sysdep/skas_ptrace.h
Simple merge

diff --cc arch/um/sys-ppc/shared/sysdep/syscalls.h
Simple merge

diff --cc arch/um/sys-ppc/sigcontext.c
Simple merge

diff --cc arch/um/sys-ppc/sysrq.c
Simple merge