usb: dwc3: gadget: Skip checking Update Transfer status

If we're not setting CMDACT (from "No Response" Update Transfer
command), then there's no point in checking for the command status. So
skip it. This can reduce a register read delay and improve performance.

Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/3dc31cf11581ae3ee82d9202dda3fc17d897d786.1638240306.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>