The purpose is to store which partition is used from
the original bdev, and it can be used to read
the further partition entry info.
Change-Id: Idbc4452846e88b486ff281c288704af80938788a
Signed-off-by: Ziye Yang <optimistyzy@gmail.com>
Reviewed-on: https://review.gerrithub.io/368486
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
6adaf829c3