[PATCH] Set ARCH_MIN_TASKALIGN on ppc32

From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

From: David Woodhouse <dwmw2@infradead.org>

Without this the task struct gets unaligned when using SLAB_DEBUG, causing
random problems with FP and Altivec.

include/asm-ppc/processor.h

@@ -121,6 +121,8 @@ struct thread_struct {
 #endif /* CONFIG_ALTIVEC */
 };
 
+#define ARCH_MIN_TASKALIGN 16
+
 #define INIT_SP		(sizeof(init_stack) + (unsigned long) &init_stack)
 
 #define INIT_THREAD { \