The function description says this should return 0 or -1 on failures.
When regions coalesce though this returns the number of coalescedregions
which is confusing and requires special handling of the return code.
On top of that no one is using the number of coalesced regions.
So let's just return 0 on success and adjust our selftests accordingly
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Caleb Connolly <caleb.connolly@linaro.org>
0f57b009e6