bpf: add XBox Elite 2 wireless controller fix
When using the XBox Wireless Controller Elite 2 over Bluetooth, the device exports the paddle on the back of the device as a single bitfield value of usage "Assign Selection".
The kernel doesn't process those usages properly and report KEY_UNKNOWN for it.
SDL doesn't know how to interprete that KEY_UNKNOWN and thus ignores the paddles.
Given that over USB the kernel uses BTN_TRIGGER_HAPPY[5-8], we can tweak the report descriptor to make the kernel interprete it properly:
- we need an application collection of gamepad (so we have to close the current Consumer Control one)
- we need to change the usage to be buttons from 0x15 to 0x18