bnxt_en: Don't query FW when netif_running() is false.

In rare conditions like two stage OS installation, the
ethtool's get_channels function may be called when the
device is in D3 state, leading to uncorrectable PCI error.
Check netif_running() first before making any query to FW
which involves writing to BAR.

Fixes: db4723b ("bnxt_en: Check max_tx_scheduler_inputs value from firmware.")
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -806,7 +806,7 @@ static void bnxt_get_channels(struct net_device *dev,
 	int max_tx_sch_inputs;
 
 	/* Get the most up-to-date max_tx_sch_inputs. */
-	if (BNXT_NEW_RM(bp))
+	if (netif_running(dev) && BNXT_NEW_RM(bp))
 		bnxt_hwrm_func_resc_qcaps(bp, false);
 	max_tx_sch_inputs = hw_resc->max_tx_sch_inputs;