wifi: mac80211: fix potential sta-link leak

When a station is allocated, links are added but not
set to valid yet (e.g. during connection to an AP MLD),
we might remove the station without ever marking links
valid, and leak them. Fix that.

Fixes: cb71f1d1

 ("wifi: mac80211: add sta link addition/removal")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240111181514.6573998beaf8.I09ac2e1d41c80f82a5a616b8bd1d9d8dd709a6a6@changeid


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