Revert "usb: gadget: zero: Add support for interrupt EP"

This reverts commit ef11982dd7.

That commit creates a problem for some UDCs (at least musb)
where it allocates an endpoints with a 64-byte FIFO, but later
tries to use that same FIFO for 1024-byte packets.

Before implementing this, composite framework needs to be
modified so we only allocate endpoints after we know negotiated
speed, however that needs quite a bit of extra work.

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/function/f_loopback.c

@@ -289,8 +289,7 @@ static void disable_loopback(struct f_loopback *loop)
 	struct usb_composite_dev	*cdev;
 
 	cdev = loop->function.config->cdev;
-	disable_endpoints(cdev, loop->in_ep, loop->out_ep, NULL, NULL, NULL,
-			NULL);
+	disable_endpoints(cdev, loop->in_ep, loop->out_ep, NULL, NULL);
 	VDBG(cdev, "%s disabled\n", loop->function.name);
 }