[PATCH] mmdevapi/tests: Fix memory leaks (Coverity)

[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://testbot.winehq.org/JobDetails.pl?Key=34825

Your paranoid android.


=== w864 (64 bit render) ===
render.c:1025: Test failed: Position 6592 too far after playing 100ms

=== w1064 (32 bit capture) ===
capture.c:181: Test failed: Position 375 expected 0
capture.c:318: Test failed: Position 1271 gap 0