remove most of SDL_OutOfMemory() calls where SDL is the allocator.

Since commit 447b508a77, SDL_malloc,
SDL_calloc, and SDL_realloc already calls SDL_OutOfMemory().

src/audio/SDL_audio.c

@@ -1335,8 +1335,6 @@ static SDL_AudioDeviceID *GetAudioDevices(int *count, SDL_bool iscapture)
 
                 SDL_assert(devs_seen == num_devices);
                 retval[devs_seen] = 0;  // null-terminated.
-            } else {
-                SDL_OutOfMemory();
             }
         }
         SDL_UnlockRWLock(current_audio.device_hash_lock);