powerpc: Use arch/powerpc/mm and arch/powerpc/lib for 64-bit

This also puts a copy of indirect_pci.c in arch/powerpc/sysdev
so that we don't need to build in arch/ppc/syslib.

Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/sysdev/Makefile

@@ -1 +1,3 @@
-obj-$(CONFIG_MPIC)	+= mpic.o
+obj-$(CONFIG_MPIC)		+= mpic.o
+indirectpci-$(CONFIG_PPC_PMAC)	= indirect_pci.o
+obj-$(CONFIG_PPC32)		+= $(indirectpci-y)