This will eliminate one calloc() and add one small code cleanup. Change-Id: I3d67f2b073a46e04304ae5342974afecf532794b Signed-off-by: Changpeng Liu <changpeng.liu@intel.com> Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/1233 Tested-by: SPDK CI Jenkins <sys_sgci@intel.com> Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com> Reviewed-by: Jim Harris <james.r.harris@intel.com>