5669 altroot not set in zpool create when specified with -o
Author: Xin Li <delphij@freebsd.org>
Reviewed by: George Wilson <george@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
illumos/illumos-gate@c423721f9bcd45c2409ef7b73fc103ac2889f9e9