SLQB: Fix compile warnings on UMA and UP

As reported by Stephen Rothwell:

  Today's linux-next build (powerpc allnoconfig) produced this warning:

  mm/slqb.c: In function 'kmem_cache_open':
  mm/slqb.c:2180: warning: label 'error_lock' defined but not used
  mm/slqb.c:2176: warning: label 'error_cpu_array' defined but not used

  Caused by commit 8b9ffd9d52479bd17b5729c9f3acaefa90c7e585 ("slqb: dynamic
  array allocations").

  Clearly neither CONFIG_SMP not CONFIG_NUMA is set.

Fix those up by wrapping the labes in ifdef CONFIG_SMP and CONFIG_NUMA where
appropriate.

Cc: Nick Piggin <npiggin@suse.de>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

mm/slqb.c

@@ -2172,12 +2172,12 @@ error_nodes:
 error_node_array:
 #ifdef CONFIG_NUMA
 	kmem_cache_dyn_array_free(s->node_slab);
-#endif
 error_cpu_array:
+#endif
 #ifdef CONFIG_SMP
 	kmem_cache_dyn_array_free(s->cpu_slab);
-#endif
 error_lock:
+#endif
 	up_write(&slqb_lock);
 error:
 	if (flags & SLAB_PANIC)