Instead of open-coding the calculation with efx_tx_queue_partner(), use
 the functions that iterate over numbers of queues other than 2 with
 efx_for_each_channel_tx_queue().
Signed-off-by: NEdward Cree <ecree@solarflare.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>