usb: dwc3: gadget: Return success always for kick transfer in ep queue

If an error is received when issuing a start or update transfer
command, the error handler will stop all active requests (including
the current USB request), and call dwc3_gadget_giveback() to notify
function drivers of the requests which have been stopped.  Avoid
returning an error for kick transfer during EP queue, to remove
duplicate cleanup operations on the request being queued.

Fixes: 8d99087c

 ("usb: dwc3: gadget: Properly handle failed kick_transfer")
cc: stable@vger.kernel.org
Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Link: https://lore.kernel.org/r/1620410119-24971-1-git-send-email-wcheng@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>