brcmfmac: print errors if creating interface fails

This is helpful for debugging. Without this all I was getting from "iw"
command on failed creating of P2P interface was:
> command failed: Too many open files in system (-23)

Signed-off-by: Rafal Milecki <zajec5@gmail.com>
[arend@broadcom.com: reduce error prints upon iface creation]
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Reviewed-by: Julian Calaby <julian.calaby@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index ba65a93..30ac4365 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -684,20 +684,24 @@
 		return ERR_PTR(-EOPNOTSUPP);
 	case NL80211_IFTYPE_AP:
 		wdev = brcmf_ap_add_vif(wiphy, name, flags, params);
-		if (!IS_ERR(wdev))
-			brcmf_cfg80211_update_proto_addr_mode(wdev);
-		return wdev;
+		break;
 	case NL80211_IFTYPE_P2P_CLIENT:
 	case NL80211_IFTYPE_P2P_GO:
 	case NL80211_IFTYPE_P2P_DEVICE:
 		wdev = brcmf_p2p_add_vif(wiphy, name, name_assign_type, type, flags, params);
-		if (!IS_ERR(wdev))
-			brcmf_cfg80211_update_proto_addr_mode(wdev);
-		return wdev;
+		break;
 	case NL80211_IFTYPE_UNSPECIFIED:
 	default:
 		return ERR_PTR(-EINVAL);
 	}
+
+	if (IS_ERR(wdev))
+		brcmf_err("add iface %s type %d failed: err=%d\n",
+			  name, type, (int)PTR_ERR(wdev));
+	else
+		brcmf_cfg80211_update_proto_addr_mode(wdev);
+
+	return wdev;
 }
 
 static void brcmf_scan_config_mpc(struct brcmf_if *ifp, int mpc)