audio: Remove const from an SDL_bool parameter in SDL_AddAudioDevice.

src/audio/SDL_audio.c

@@ -622,7 +622,7 @@ static SDL_AudioDevice *CreateAudioPlaybackDevice(const char *name, const SDL_Au
 }
 
 // The audio backends call this when a new device is plugged in.
-SDL_AudioDevice *SDL_AddAudioDevice(const SDL_bool recording, const char *name, const SDL_AudioSpec *inspec, void *handle)
+SDL_AudioDevice *SDL_AddAudioDevice(SDL_bool recording, const char *name, const SDL_AudioSpec *inspec, void *handle)
 {
     // device handles MUST be unique! If the target reuses the same handle for hardware with both recording and playback interfaces, wrap it in a pointer you SDL_malloc'd!
     SDL_assert(SDL_FindPhysicalAudioDeviceByHandle(handle) == NULL);

src/audio/SDL_sysaudio.h

@@ -69,7 +69,7 @@ extern void SDL_SetupAudioResampler(void);
 /* Backends should call this as devices are added to the system (such as
    a USB headset being plugged in), and should also be called for
    for every device found during DetectDevices(). */
-extern SDL_AudioDevice *SDL_AddAudioDevice(const SDL_bool recording, const char *name, const SDL_AudioSpec *spec, void *handle);
+extern SDL_AudioDevice *SDL_AddAudioDevice(SDL_bool recording, const char *name, const SDL_AudioSpec *spec, void *handle);
 
 /* Backends should call this if an opened audio device is lost.
    This can happen due to i/o errors, or a device being unplugged, etc. */