x86-64, NUMA: Factor out memblk handling into numa_{add|register}_memblk()

Factor out memblk handling from srat_64.c into two functions in
numa_64.c.  This patch doesn't introduce any behavior change.  The
next patch will make all init methods use these functions.

- v2: Fixed build failure on 32bit due to misplaced NR_NODE_MEMBLKS.
      Reported by Ingo.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/include/asm/numa.h

@@ -5,6 +5,9 @@
 #include <asm/apicdef.h>
 
 #ifdef CONFIG_NUMA
+
+#define NR_NODE_MEMBLKS		(MAX_NUMNODES*2)
+
 /*
  * __apicid_to_node[] stores the raw mapping between physical apicid and
  * node and is used to initialize cpu_to_node mapping.