Since accessing Bluetooth prompts the user for permission on both Android and iOS, and we only need it for Steam Controller support, we'll leave it off by default. You can enable it by setting the hint SDL_HINT_JOYSTICK_HIDAPI_STEAM to "1" before calling SDL_Init()
Fixes https://github.com/libsdl-org/SDL/issues/4952
This prevents conflicts with hidapi linked with applications, as well as allowing applications to make use of HIDAPI on Android and other platforms that might not normally have an implementation available.
If you enable this, you'll need to link with CoreBluetooth.framework and add something like this to your Info.plist:
<key>NSBluetoothPeripheralUsageDescription</key>
<string>MyApp would like to remain connected to nearby bluetooth Game Controllers and Game Pads even when you're not using the app.</string>