plugins/sixaxis: Fix get_js_number() for devices connected via BT

plugins/sixaxis: Fix get_js_number() for devices connected via BT

Match hid devices and input devices using HID_UNIQ and UNIQ when these
are available, this is the correct way to get matching devices when the
controllers are connected via BT (UNIQ refers to the device bdaddr, PHYS
is the adapter bdaddr, so matching against PHYS will result in all
devices with the same LED number).

Fall back to HID_PHYS and PHYS when needed, hid devices do not define
HID_UNIQ when connected via USB.