ion: chunk_heap: fix leak in allocated counter

buffer->size is controlled by the outer ion layer, don't modify it
inside the heap.  Instead, compute the rounded up allocated size
on demand.

Change-Id: I288ffc1221ce96cfe2591468502ac3279065bde4
Signed-off-by: Colin Cross <ccross@android.com>
ion: add free list size to heap debug files

Change-Id: I3c6309afdbd661a2f870fd1ba3fea9543e229882
Signed-off-by: Colin Cross <ccross@android.com>