usb: mtu3: clear test_mode flag when reset

Clear test_mode flag when the gadget is reset by host, otherwise
will affect the next test item.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed