hiqnet: Use correct filter names; Fix specification of hf_dhcp

   "foo.flags..." --> "hiqnet.flags...";
   Use BASE_NONE for hf_dchp.

Change-Id: Ic3ca4754a1daeefc831dbfcd6a280fe19f8efbf3
Reviewed-on: https://code.wireshark.org/review/5240
Reviewed-by: Bill Meier <wmeier@newsguy.com>