OS-4191 blown assert on lx zone with delegated dataset

*** 470,481 ****
          while ((elem = nvlist_next_nvpair(nv, elem)) != NULL) {
                  struct vnode *vp;
                  ASSERT(dvp->v_count > 0);
                  rc = VOP_LOOKUP(dvp, nvpair_name(elem), &vp, NULL, 0,
                      NULL, kcred, NULL, 0, NULL);
!                 /* should either work, or not be visible from a zone */
!                 ASSERT(rc == 0 || rc == ENOENT);
                  if (rc == 0)
                          VN_RELE(vp);
                  pools++;
          }
          nvlist_free(nv);
--- 470,483 ----
          while ((elem = nvlist_next_nvpair(nv, elem)) != NULL) {
                  struct vnode *vp;
                  ASSERT(dvp->v_count > 0);
                  rc = VOP_LOOKUP(dvp, nvpair_name(elem), &vp, NULL, 0,
                      NULL, kcred, NULL, 0, NULL);
!                 /*
!                  * should either work or we should get an error if this should
!                  * not be visible from the zone, or disallowed in the zone
!                  */
                  if (rc == 0)
                          VN_RELE(vp);
                  pools++;
          }
          nvlist_free(nv);