wireless: T2427: migrate to use common configdict and vlan functions
wireless: T2427: migrate to use common configdict and vlan functions

Other interfaces were previously migrated, but this one was forgotten,
causing a commit error:

    File "/usr/libexec/vyos/conf_mode/interfaces-wireless.py", line 621,
          in verify
      verify_vlan_config(wifi)
    File "/usr/lib/python3/dist-packages/vyos/ifconfig_vlan.py", line 155,
          in verify_vlan_config
      for vif in config['vif'].values():
  AttributeError: 'list' object has no attribute 'values'

vyos/vyos-1x,vyos/vyos-1x,vyos/vyos-1x,vyos/vyos-1x