Fixed mingw64 32-bit build, which does have the correct structure definitions
diff --git a/src/audio/winmm/SDL_winmm.c b/src/audio/winmm/SDL_winmm.c
index 908c37e..71a5dc9 100644
--- a/src/audio/winmm/SDL_winmm.c
+++ b/src/audio/winmm/SDL_winmm.c
@@ -33,8 +33,8 @@
#include "../SDL_audio_c.h"
#include "SDL_winmm.h"
-/*====== WORKAROUND for MinGW's WinAPI header where those structures are being missed ======*/
-#if defined(__MINGW32__) && !defined(__MINGW64__)
+/* MinGW32 mmsystem.h doesn't include these structures */
+#if defined(__MINGW32__) && defined(_MMSYSTEM_H)
typedef struct tagWAVEINCAPS2W
{
@@ -65,8 +65,7 @@ typedef struct tagWAVEOUTCAPS2W
GUID NameGuid;
} WAVEOUTCAPS2W,*PWAVEOUTCAPS2W,*NPWAVEOUTCAPS2W,*LPWAVEOUTCAPS2W;
-#endif /* defined(__MINGW32__) && !defined(__MINGW64__) */
-/*==========================================================================================*/
+#endif /* defined(__MINGW32__) && defined(_MMSYSTEM_H) */
#ifndef WAVE_FORMAT_IEEE_FLOAT
#define WAVE_FORMAT_IEEE_FLOAT 0x0003