Use the white box validation and test rig added as part of the
sys_heap work. Add a layer that puts hashed cookies into the blocks
to detect corruption, check the validity state after every operation,
and enumerate a few different usage patterns:
+ Small heap, "real world" allocation where the heap is about half
full and most allocations succeed.
+ Small heap, "fragmentation runaway" scenario where most allocations
start failing, but the heap must remain consistent.
+ Big heap. We can't test this with the same exhaustive coverage
(many re/allocations for every byte of storage) for performance
reasons, but we do what we can.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>