5310 Remove always true tests for non-NULL ds->ds_phys
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Will Andrews <willa@spectralogic.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@d808a4fc6ac40e878a28e96f1ad7dd2ec439bfbf