mmdevapi/tests: Compile with -D__WINESRC__.

[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
https://newtestbot.winehq.org/JobDetails.pl?Key=2797

Your paranoid android.


=== w7pro64 (32 bit render) ===
render.c:662: Test failed: Wait(event) after Stop gave 102