sfc: Test only the first pair of TX queues

This makes no immediate difference, but we definitely do not want
to test all TX queues once we allocate a pair of TX queues to each
channel.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/selftest.c b/drivers/net/sfc/selftest.c
index 0106b1d..3a16e06 100644
--- a/drivers/net/sfc/selftest.c
+++ b/drivers/net/sfc/selftest.c
@@ -616,8 +616,8 @@
 			goto out;
 		}
 
-		/* Test every TX queue */
-		efx_for_each_tx_queue(tx_queue, efx) {
+		/* Test both types of TX queue */
+		efx_for_each_channel_tx_queue(tx_queue, &efx->channel[0]) {
 			state->offload_csum = (tx_queue->queue ==
 					       EFX_TX_QUEUE_OFFLOAD_CSUM);
 			rc = efx_test_loopback(tx_queue,