libertas: fix error return code in if_cs_probe()

Fix to return -ENODEV in the unknown model error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <[e-mail]>
Acked-by: Dan Williams <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

drivers/net/wireless/libertas/if_cs.c

···
 	if (card->model == MODEL_UNKNOWN) {
 		pr_err("unsupported manf_id 0x%04x / card_id 0x%04x\n",
 		       p_dev->manf_id, p_dev->card_id);
+		ret = -ENODEV;
 		goto out2;
 	}