powerpc/mm: Fix printk type warning in mmu_context_nohash

We need to use %zu instead of %d when printing a sizeof()
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/mm/mmu_context_nohash.c

@@ -380,7 +380,7 @@ void __init mmu_context_init(void)
 #endif
 
 	printk(KERN_INFO
-	       "MMU: Allocated %d bytes of context maps for %d contexts\n",
+	       "MMU: Allocated %zu bytes of context maps for %d contexts\n",
 	       2 * CTX_MAP_SIZE + (sizeof(void *) * (last_context + 1)),
 	       last_context - first_context + 1);