wifi: mac80211: handle WLAN_HT_ACTION_NOTIFY_CHANWIDTH async

wifi: mac80211: handle WLAN_HT_ACTION_NOTIFY_CHANWIDTH async

If this action frame, with the value of IEEE80211_HT_CHANWIDTH_ANY,
arrives right after a beacon that changed the operational bandwidth from
20 MHz to 40 MHz, then updating the rate control bandwidth to 40 can
race with updating the chanctx width (that happens in the beacon
proccesing) back to 40 MHz:

cpu0					cpu1

ieee80211_rx_mgmt_beacon
ieee80211_config_bw
ieee80211_link_change_chanreq
(*)ieee80211_link_update_chanreq
					ieee80211_rx_h_action
					(**)ieee80211_sta_cur_vht_bw
(***) ieee80211_recalc_chanctx_chantype

in (**), the maximum between the capability width and the bss width is
returned. But the bss width was just updated to 40 in (*),
so the action frame handling code will increase the width of the rate
control before the chanctx was increased (in ***), leading to a FW error
(at least in iwlwifi driver. But this is wrong regardless).

Fix this by simply handling the action frame async, so it won't race
with the beacon proccessing.

Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218632
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250709233537.bb9dc6f36c35.I39782d6077424e075974c3bee4277761494a1527@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>