sysclk-lwla: Set USB device configuration

sysclk-lwla: Set USB device configuration

After opening the USB device, set the device configuration to 1.
Actually, do it twice, just as the vendor driver seems to do. This
is supposed to trigger a lightweight reset of the device.

Originally, I omitted this reset sequence from the sigrok driver
because it simply did not work at all for me. However, it does seem
to work now, so that may have been a problem in libusb or the kernel
which is now fixed.

With some luck, this change may finally fix #327.