powerpc/pseries: Move lparcfg.c to platforms/pseries

This file is entirely pseries specific nowadays, so move it out
of arch/powerpc/kernel where it doesn't belong anymore.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --cc arch/powerpc/kernel/Makefile
Simple merge

diff --cc arch/powerpc/platforms/pseries/Makefile
Simple merge

diff --cc arch/powerpc/platforms/pseries/lparcfg.c
Simple merge