Fix -Wundef warnings due to use of unguarded SDL_AUDIO_DRIVER_AAUDIO

src/audio/SDL_audio.c

@@ -58,7 +58,7 @@ static const AudioBootStrap *const bootstrap[] = {
 #ifdef SDL_AUDIO_DRIVER_COREAUDIO
     &COREAUDIO_bootstrap,
 #endif
-#if SDL_AUDIO_DRIVER_AAUDIO
+#ifdef SDL_AUDIO_DRIVER_AAUDIO
     &aaudio_bootstrap,
 #endif
 #if SDL_AUDIO_DRIVER_OPENSLES

src/audio/aaudio/SDL_aaudio.c

@@ -20,7 +20,7 @@
 */
 #include "SDL_internal.h"
 
-#if SDL_AUDIO_DRIVER_AAUDIO
+#ifdef SDL_AUDIO_DRIVER_AAUDIO
 
 #include "../SDL_audio_c.h"
 #include "../../core/android/SDL_android.h"

src/video/android/SDL_androidevents.c

@@ -49,7 +49,7 @@ static void openslES_ResumeDevices(void)
 static void openslES_PauseDevices(void) {}
 #endif
 
-#if !defined(SDL_AUDIO_DISABLED) && SDL_AUDIO_DRIVER_AAUDIO
+#if !defined(SDL_AUDIO_DISABLED) && defined(SDL_AUDIO_DRIVER_AAUDIO)
 extern void aaudio_ResumeDevices(void);
 extern void aaudio_PauseDevices(void);
 SDL_bool aaudio_DetectBrokenPlayState(void);