[PATCH v6 0/2] MR3854: winmm: Avoid use of hardcoded return values.

[Alistair Leslie-Hughes (＠alesliehughes)]

Based on patch by Michael Müller.

--
  v6: winmm: MCI_MapMsgAtoW return error code directly instead of a tri-value.
      winmm: Always call MCI_UnmapMsgAtoW in mciSendCommandA.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/3854