usb: dwc3: gadget: move isoc endpoint check to unlocked set_halt

__dwc3_gadget_ep_set_halt() is the function which
handles the actual halt feature. In order to cope
with some extra cleanup comming as a follow-up patch
let's move the isochronous endpoint check there too.
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -1208,6 +1208,11 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value)
 	struct dwc3				*dwc = dep->dwc;
 	int					ret;
 
+	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
+		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
+		return -EINVAL;
+	}
+
 	memset(&params, 0x00, sizeof(params));
 
 	if (value) {
@@ -1241,15 +1246,7 @@ static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
 	int				ret;
 
 	spin_lock_irqsave(&dwc->lock, flags);
-
-	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
-		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
-		ret = -EINVAL;
-		goto out;
-	}
-
 	ret = __dwc3_gadget_ep_set_halt(dep, value);
-out:
 	spin_unlock_irqrestore(&dwc->lock, flags);
 
 	return ret;