device filtering support

[Pete Batard]

On 2012.02.04 14:11, Pete Batard wrote:
>> so that will keep a lot of
>> duplicate codes inside the Windows backend.

Also with regards to this, IIRC, the last time I went through the 
K+WinUSB implementation, the "duplicated" code was akin to:

if (has_K_support)
   call WinUSBK with parameters x, y, z
else
   call WinUSB with parameters x, y, z

Again, Travis did great work making the libubsK and WinUSB APIs 
compatible, so there's hardly anything duplicated in code that supports 
either standalone WinUSB or K.

Regards,

/ete