usb: gadget: f_phonet: unlock in error case

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/f_phonet.c

@@ -434,6 +434,7 @@ static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 			    config_ep_by_speed(gadget, f, fp->out_ep)) {
 				fp->in_ep->desc = NULL;
 				fp->out_ep->desc = NULL;
+				spin_unlock(&port->lock);
 				return -EINVAL;
 			}
 			usb_ep_enable(fp->out_ep);