Try to remove assumption that zone's root vnode is marked VROOT

*** 728,737 ****
--- 728,738 ----
           * its pseudonode.
           * Note - for VROOT exports the implicitly allowed flavors were
           * transferred from the PSEUDO export in exportfs()
           */
          if (isadd && !(exip->exi_vp->v_flag & VROOT) &&
+             !VN_IS_CURZONEROOT(exip->exi_vp) &&
              tnode->tree_vis->vis_seccnt > 0) {
                  srv_secinfo_add(&exip->exi_export.ex_secinfo,
                      &exip->exi_export.ex_seccnt, tnode->tree_vis->vis_secinfo,
                      tnode->tree_vis->vis_seccnt, FALSE);
          }
*** 2074,2084 ****
                  /*
                   * We have just failed finding a matching export.
                   * If we're at the root of this filesystem, then
                   * it's time to stop (with failure).
                   */
!                 if (vp->v_flag & VROOT) {
                          error = EINVAL;
                          break;
                  }
  
                  if (walk != NULL)
--- 2075,2085 ----
                  /*
                   * We have just failed finding a matching export.
                   * If we're at the root of this filesystem, then
                   * it's time to stop (with failure).
                   */
!                 if ((vp->v_flag & VROOT) || VN_IS_CURZONEROOT(vp)) {
                          error = EINVAL;
                          break;
                  }
  
                  if (walk != NULL)