usb: dwc3: Fixed a typo in comments

Fixed a typo in comments
Signed-off-by: Mickael Maison <mickael.maison@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/gadget.c

@@ -2077,7 +2077,7 @@ static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
 	 * We have discussed this with the IP Provider and it was
 	 * suggested to giveback all requests here, but give HW some
 	 * extra time to synchronize with the interconnect. We're using
-	 * an arbitraty 100us delay for that.
+	 * an arbitrary 100us delay for that.
 	 *
 	 * Note also that a similar handling was tested by Synopsys
 	 * (thanks a lot Paul) and nothing bad has come out of it.