wil6210: do not attempt FW recovery if interface is down

When interface is down, recovery flow should not be attempted.
Next ndo_open() will trigger target reset, that is FW recovery.

Doing recovery while interface is down cause internal "up", leaving
internal driver state in conflict with network stack. Then, when network
stack will call ndo_open(), kernel oops will be triggered.
Signed-off-by: NVladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/wil6210/main.c

@@ -223,6 +223,11 @@ static void wil_fw_error_worker(struct work_struct *work)
 
 	wil_dbg_misc(wil, "fw error worker\n");
 
+	if (!netif_running(wil_to_ndev(wil))) {
+		wil_info(wil, "No recovery - interface is down\n");
+		return;
+	}
+
 	/* increment @recovery_count if less then WIL6210_FW_RECOVERY_TO
 	 * passed since last recovery attempt
 	 */