x86, NUMA: trivial cleanups

* Kill no longer used struct bootnode.

* Kill dangling declaration of pxm_to_nid() in numa_32.h.

* Make setup_node_bootmem() static.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

arch/x86/include/asm/numa_32.h

@@ -3,8 +3,6 @@
 
 extern int numa_off;
 
-extern int pxm_to_nid(int pxm);
-
 #ifdef CONFIG_HIGHMEM
 extern void set_highmem_pages_init(void);
 #else