Update msd_fabric_networks.j2 (#483)

Author: ccoueffe

roles/dtc/common/templates/ndfc_networks/msd_fabric/msd_fabric_networks.j2

@@ -37,7 +37,7 @@
   int_desc: {{ net['int_desc'] | default(defaults.vxlan.overlay.networks.net_description) }}
   mtu_l3intf: {{ net['mtu_l3intf'] | default(defaults.vxlan.overlay.networks.mtu_l3intf) }}
   route_target_both: {{ net['route_target_both'] | default(defaults.vxlan.overlay.networks.route_target_both) }}
-  route_tag: {{ net['route_tag'] | default(defaults.vxlan.overlay.networks.route_tag) }}
+  routing_tag: {{ net['route_tag'] | default(defaults.vxlan.overlay.networks.route_tag) }}
 {# ------------------------------------------------------ #}
 {# Attach Group Section #}
 {# ------------------------------------------------------ #}