staging: wfx: take advantage of ieee80211_{stop/start}_queues

staging: wfx: take advantage of ieee80211_{stop/start}_queues

Instead of maintaining stop status for each queue, we can just maintain
a global status for all queues.

In add, wfx_tx_queues_{lock/unlock} are only used when no more
tx_policies are available. Therefore, the counter of recursive locks
("tx_locked_cnt") is useless.

So, wfx_tx_queues_{lock/unlock} can be replaced by
ieee80211_{stop/start}_queues.

Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200401110405.80282-4-Jerome.Pouiller@silabs.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>