usb: gadget: omap_udc: remove unneeded semicolon

Fix the following coccicheck warning:

drivers/usb/gadget/udc/omap_udc.c:2579:2-3: Unneeded semicolon

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>