fix memory leak in iface_do_create
fix memory leak in iface_do_create

   use smap_destroy instead of smap_clear to free up
      local smap clone

Change-Id: I5c888f1de32cfca868c551d0cfd414c8b16b8d96
Signed-off-by: Michael Nadler <528b909787175aa99d5953d8e07d9292796fa106@hpe.com>

open-switch/ops-switchd,open-switch/ops-switchd,open-switch/ops-switchd