ieee80211; Rename some hf[] display filter names to fix dups and for clarity.

Backported (with no changes) from master 1aeab74
See: https://code.wireshark.org/review/5534

Change-Id: Ibcca2d7f85130b4a5a74808d88735513cfc0b580
Reviewed-on: https://code.wireshark.org/review/5587
Reviewed-by: Bill Meier <wmeier@newsguy.com>