[PATCH] xaudio2_7/tests: Remove redundant not-NULL checks (coccinellery)

[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=49023

Your paranoid android.


=== debian9 (32 bit report) ===

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=== debian9 (32 bit WoW report) ===

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