dinput: Combine ASCII and Unicode device create callbacks. Add tests. (try 2)

[Marvin]

Hi,

While running your changed tests on Windows, I think I found new failures.
Being a bot and all I'm not very good at pattern recognition, so I might be
wrong, but could you please double-check?
Full results can be found at
http://testbot.winehq.org/JobDetails.pl?Key=8488

Your paranoid android.


=== WNT4WSSP6 (32 bit device) ===
device.c:168: Test failed: DirectInputCreate() failed: 80040154