Double free in direct sound capture

[Michael Karcher]

Hello developers

I was running the testcases with warn+heap, and noted some warnings from
dsound:capture. They are caused by double free calls, and only happen
with winealsa.drv, not with wineoss.drv. The following patch happens to
makes the messages disappear. Could somebody with some knowledge about
wine's DirectSound implementation please look into this issue and find a
proper fix?

Regards,
  Michael Karcher