[PATCH] ppc32: Fix building for Motorola Sandpoint with O=

Since we directly -include $(clear_L2_L3) when needed, we need to point to
the full path of it.
Signed-off-by: Tom Rini <trini@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc/boot/simple/Makefile

@@ -41,7 +41,7 @@ end-y := elf
 # if present on 'classic' PPC.
 cacheflag-y	:= -DCLEAR_CACHES=""
 # This file will flush / disable the L2, and L3 if present.
-clear_L2_L3	:= $(boot)/simple/clear.S
+clear_L2_L3	:= $(srctree)/$(boot)/simple/clear.S
 
 #
 # See arch/ppc/kconfig and arch/ppc/platforms/Kconfig