tablet copy client: delete WAL data using existing function

I thought this might be needed for correctness (if Log::DeleteOnDiskData did
something beyond a recursive deletion), but it's not. Nevertheless, it seems
more robust, if DeleteOnDiskData _did_ were changed to do something
interesting in the future.

Change-Id: Ic18d11a3d857ab9a29a82d9f7ebe72f33737e25d
Reviewed-on: http://gerrit.cloudera.org:8080/15077
Reviewed-by: Andrew Wong <awong@cloudera.com>
Tested-by: Kudu Jenkins
Reviewed-by: Alexey Serbin <aserbin@cloudera.com>
2 files changed