[PATCH] x86-64: clean up sparsemem memory_present call

Eliminate arch specific memory_present call x86_64 NUMA by utilizing
sparse_memory_present_with_active_regions.

Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>