usb: cdns3: fix incorrect calculation of ep_buf_size when more than one config

Previously, the cdns3_gadget_check_config() function in the cdns3 driver
mistakenly calculated the ep_buf_size by considering only one
configuration's endpoint information because "claimed" will be clear after
call usb_gadget_check_config().

The fix involves checking the private flags EP_CLAIMED instead of relying
on the "claimed" flag.

Fixes: dce4944 ("usb: cdns3: allocate TX FIFO size according to composite EP number")
Cc: stable <stable@kernel.org>
Reported-by: Ravi Gunasekaran <r-gunasekaran@ti.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Tested-by: Ravi Gunasekaran <r-gunasekaran@ti.com>
Link: https://lore.kernel.org/r/20230707230015.494999-2-Frank.Li@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: nxpfrankli

drivers/usb/cdns3/cdns3-gadget.c

@@ -3015,12 +3015,14 @@ static int cdns3_gadget_udc_stop(struct usb_gadget *gadget)
 static int cdns3_gadget_check_config(struct usb_gadget *gadget)
 {
 	struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
+	struct cdns3_endpoint *priv_ep;
 	struct usb_ep *ep;
 	int n_in = 0;
 	int total;
 
 	list_for_each_entry(ep, &gadget->ep_list, ep_list) {
-		if (ep->claimed && (ep->address & USB_DIR_IN))
+		priv_ep = ep_to_cdns3_ep(ep);
+		if ((priv_ep->flags & EP_CLAIMED) && (ep->address & USB_DIR_IN))
 			n_in++;
 	}