Call update_extra_dhcp_opts_on_port on port update
Call update_extra_dhcp_opts_on_port on port update

Change-Id: I330375cfd9e3e488f6e2c5efd7a8a89dd8ad4ecf

openstack/dragonflow,FrankDuan/df_code,FrankDuan/df_code,openstack/dragonflow,FrankDuan/df_code,openstack/dragonflow