It has no user now

Also print out info about adding/removing active regions.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>