wifi: mac80211: Do not use "non-MLD AP" syntax

Instead clarify the cases where link ID == 0 is intended
for an AP STA that is not part of an AP MLD.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230611121219.77236a2e26ad.I8193ca8e236c9eb015870471f77a7d5134da3156@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>