usb: dwc3: ep0: Fix delay status handling

If we want to send a control status on our own time (through
delayed_status), make sure to handle a case where we may queue the
delayed status before the host requesting for it (when XferNotReady
is generated). Otherwise, the driver won't send anything because it's
not EP0_STATUS_PHASE yet. To resolve this, regardless whether
dwc->ep0state is EP0_STATUS_PHASE, make sure to clear the
dwc->delayed_status flag if dwc3_ep0_send_delayed_status() is called.
The control status can be sent when the host requests it later.

Cc: <stable@vger.kernel.org>
Fixes: d97c78a1 ("usb: dwc3: gadget: END_TRANSFER before CLEAR_STALL command")
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>