wil6210: properly initialize discovery_expired_work

Upon driver rmmod, cancel_work_sync() can be invoked on
p2p.discovery_expired_work before this work struct was initialized.
This causes a WARN_ON with newer kernel version.

Add initialization of discovery_expired_work inside wil_vif_init().
Signed-off-by: Dedy Lansky <dlansky@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -284,6 +284,7 @@ static void wil_vif_init(struct wil6210_vif *vif)
 
 	INIT_WORK(&vif->probe_client_worker, wil_probe_client_worker);
 	INIT_WORK(&vif->disconnect_worker, wil_disconnect_worker);
+	INIT_WORK(&vif->p2p.discovery_expired_work, wil_p2p_listen_expired);
 	INIT_WORK(&vif->p2p.delayed_listen_work, wil_p2p_delayed_listen_work);
 	INIT_WORK(&vif->enable_tx_key_worker, wil_enable_tx_key_worker);