Windows: Allow claiming any interface in composite device using WinUSB

Issue reported by Benjamin Dobell, see #48. The call to
WinUsb_QueryInterfaceSettings() is removed since it doesn't work
on any other interface but the first (a WinUSB limitation).

This allows the use of WinUSB.sys in lieu of the usbccgp.sys
"USB Generic Parent" default driver for composite devices.