[PATCH] mstask: Avoid using the comma operator

[Marvin]

Hi,

While running your changed tests, 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=49839

Your paranoid android.


=== debian9b (64 bit WoW report) ===

mstask:
task_scheduler.c:498: Test failed: got 0x80070020
task_scheduler.c:295: Test failed: got 0x80070020