wifi: cfg80211: scan: skip duplicate RNR entries

wifi: cfg80211: scan: skip duplicate RNR entries

There really shouldn't be duplicate entries when we give
the list to the driver, and since we already have a list
it's easy to avoid.

While at it, remove the unnecessary allocation there.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250101070249.b0012c70f503.Id6fcad979434c1437340aa283abae2906345cca1@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>