usb: gadget: f_uac1: configure endpoint before using it

UAC1 forget to do it.
Signed-off-by: Xuebing Wang <xbing6@gmail.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/function/f_uac1.c

@@ -584,6 +584,7 @@ static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 
 	if (intf == 1) {
 		if (alt == 1) {
+			config_ep_by_speed(cdev->gadget, f, out_ep);
 			usb_ep_enable(out_ep);
 			out_ep->driver_data = audio;
 			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);