usb: gadget: f_uac2: eliminate abuse of ep->driver data

Since ep->driver_data is not used for endpoint claiming, neither for
enabled/disabled state storing, we can reduce number of places where
we read or modify it's value, as now it has no particular meaning for
function or framework logic.

In case of f_uac2, ep->driver_data was used only for endpoint claiming
and marking endpoints as enabled, so we can simplify code by reducing
it.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/function/f_uac2.c

@@ -1081,14 +1081,12 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		goto err;
 	}
-	agdev->out_ep->driver_data = agdev;
 
 	agdev->in_ep = usb_ep_autoconfig(gadget, &fs_epin_desc);
 	if (!agdev->in_ep) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 		goto err;
 	}
-	agdev->in_ep->driver_data = agdev;
 
 	uac2->p_prm.uac2 = uac2;
 	uac2->c_prm.uac2 = uac2;
@@ -1132,10 +1130,6 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 err:
 	kfree(agdev->uac2.p_prm.rbuf);
 	kfree(agdev->uac2.c_prm.rbuf);
-	if (agdev->in_ep)
-		agdev->in_ep->driver_data = NULL;
-	if (agdev->out_ep)
-		agdev->out_ep->driver_data = NULL;
 	return -EINVAL;
 }
 
@@ -1583,11 +1577,6 @@ static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
 	prm = &agdev->uac2.c_prm;
 	kfree(prm->rbuf);
 	usb_free_all_descriptors(f);
-
-	if (agdev->in_ep)
-		agdev->in_ep->driver_data = NULL;
-	if (agdev->out_ep)
-		agdev->out_ep->driver_data = NULL;
 }
 
 static struct usb_function *afunc_alloc(struct usb_function_instance *fi)