Cross-platform identifiers

Major platform identifiers share many numeric report slots, but write named constants:

cross-platform-identifiers.gpc

int confirm_button;

init {
    switch(get_controller()) {
        case PIO_PS5: { confirm_button = PS5_CROSS; break; }
        case PIO_PS4: { confirm_button = PS4_CROSS; break; }
        case PIO_XB1: { confirm_button = XB1_A; break; }
        default: { confirm_button = PS5_CROSS; break; }
    }
}

Do not assume touch, motion, mute, paddles, adaptive triggers, or extended identifiers align across protocols.