wifi: iwlwifi: release TXQ lock during reclaim

wifi: iwlwifi: release TXQ lock during reclaim

Much of the work during reclaim can be done without holding the TXQ
lock and releasing the lock means that command submission can happen at
the same time.

Add a new reclaim_lock to prevent parallel cleanup. Release the lock
while working with an internal copy of the txq->read_ptr and only take
the lock again when updating the read pointer after the cleanup is done.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20240703125541.2a81021d49ac.I53698ae92fb75a0461d41176db115462cf8be1cd@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>