[PATCH] pgdat allocation for new node add (get node id by acpi)

This is to find node id from acpi's handle of memory_device in DSDT.  _PXM for
the new node can be found by acpi_get_pxm() by using new memory's handle.  So,
node id can be found by pxm_to_nid_map[].

  This patch becomes simpler than v2 of node hot-add patch.
  Because old add_memory() function doesn't have node id parameter.
  So, kernel must find its handle by physical address via DSDT again.
  But, v3 just give node id to add_memory() now.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>