From: Matthew Dobson <colpatch@us.ibm.com>

Remove MAX_NR_NODES.  This value is only used in a couple of places, and
it's incorrectly used in all those places as far as I can tell.  Replace
with MAX_NUMNODES.  Create MAX_NODES_SHIFT and use this value to check
NODES_SHIFT is appropriate.  A possible future patch should make
MAX_NODES_SHIFT vary based on 32 vs.  64 bit archs.