USB: gadget: Fix typo (s/EBUSY/-EBUSY) in ci13xxx_udc

Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/ci13xxx_udc.c

@@ -1864,7 +1864,7 @@ __acquires(mEp->lock)
 		}
 	}
 
-	if (retval == EBUSY)
+	if (retval == -EBUSY)
 		retval = 0;
 	if (retval < 0)
 		dbg_event(_usb_addr(mEp), "DONE", retval);