[POWERPC] Provide access to arch/powerpc include path on ppc64

There does not appear to be any reason that we shouldn't just have
-Iarch/$(ARCH) on both ppc32 and ppc64 builds.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

arch/powerpc/Makefile

@@ -71,13 +71,11 @@ endif
 
 LDFLAGS_vmlinux	:= -Bstatic
 
-CPPFLAGS-$(CONFIG_PPC32) := -Iarch/$(ARCH)
-AFLAGS-$(CONFIG_PPC32)	:= -Iarch/$(ARCH)
 CFLAGS-$(CONFIG_PPC64)	:= -mminimal-toc -mtraceback=none  -mcall-aixdesc
-CFLAGS-$(CONFIG_PPC32)	:= -Iarch/$(ARCH) -ffixed-r2 -mmultiple
-KBUILD_CPPFLAGS	+= $(CPPFLAGS-y)
-KBUILD_AFLAGS	+= $(AFLAGS-y)
-KBUILD_CFLAGS	+= -msoft-float -pipe $(CFLAGS-y)
+CFLAGS-$(CONFIG_PPC32)	:= -ffixed-r2 -mmultiple
+KBUILD_CPPFLAGS	+= -Iarch/$(ARCH)
+KBUILD_AFLAGS	+= -Iarch/$(ARCH)
+KBUILD_CFLAGS	+= -msoft-float -pipe -Iarch/$(ARCH) $(CFLAGS-y)
 CPP		= $(CC) -E $(KBUILD_CFLAGS)
 
 CHECKFLAGS	+= -m$(CONFIG_WORD_SIZE) -D__powerpc__ -D__powerpc$(CONFIG_WORD_SIZE)__