sfc: siena: eliminate xdp_rxq_info_valid using XDP base API

Commit d48523cb88e0 ("sfc: Copy shared files needed for Siena (part 2)")
use xdp_rxq_info_valid to track failures of xdp_rxq_info_reg().
However, this driver-maintained state becomes redundant since the XDP
framework already provides xdp_rxq_info_is_reg() for checking registration
status.

Signed-off-by: Fushuai Wang <[e-mail]>
Acked-by: Edward Cree <[e-mail]>
Reviewed-by: Larysa Zaremba <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/ethernet/sfc/siena/net_driver.h

···
  * @recycle_count: RX buffer recycle counter.
  * @slow_fill: Timer used to defer efx_nic_generate_fill_event().
  * @xdp_rxq_info: XDP specific RX queue information.
- * @xdp_rxq_info_valid: Is xdp_rxq_info valid data?.
  */
 struct efx_rx_queue {
 	struct efx_nic *efx;
···
 	/* Statistics to supplement MAC stats */
 	unsigned long rx_packets;
 	struct xdp_rxq_info xdp_rxq_info;
-	bool xdp_rxq_info_valid;
 };
 
 enum efx_sync_events_state {

drivers/net/ethernet/sfc/siena/rx_common.c

···
 			  "Failure to initialise XDP queue information rc=%d\n",
 			  rc);
 		efx->xdp_rxq_info_failed = true;
-	} else {
-		rx_queue->xdp_rxq_info_valid = true;
 	}
 
 	/* Set up RX descriptor ring */
···
 
 	efx_fini_rx_recycle_ring(rx_queue);
 
-	if (rx_queue->xdp_rxq_info_valid)
+	if (xdp_rxq_info_is_reg(&rx_queue->xdp_rxq_info))
 		xdp_rxq_info_unreg(&rx_queue->xdp_rxq_info);
-
-	rx_queue->xdp_rxq_info_valid = false;
 }
 
 void efx_siena_remove_rx_queue(struct efx_rx_queue *rx_queue)