usb: gadget: uvc: Prevent buffer overflow in setup handler

In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: uvc: Prevent buffer overflow in setup handler

Setup function uvc_function_setup permits control transfer

requests with up to 64 bytes of payload (UVC_MAX_REQUEST_SIZE),

data stage handler for OUT transfer uses memcpy to copy req->actual

bytes to uvc_event->data.data array of size 60. This may result

in an overflow of 4 bytes.