NOT READY FOR MERGING!
Only works with NUMA off on 2.6.13.  On 2.6.13 with NUMA on free_hot_cold_page
calls __free_pages_bulk, which then trips BUG_ON(bad_range(zone,page));  This
does not happen on 2.6.13-rc1 kernels. Released under the release early
release often doctrine.

This patch splits the percpu allocations into two types.  Kernel reclaimable
and kernel non-reclaimable types are considered one PCPU_KERNEL type and user
types are PCPU_USER type.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>