WiimoteScannerAndroid::FindAttachedWiimotes() added every device
connected through the DolphinBar to the Wii Remote results, with a
TODO noting that balance boards were not differentiated. As a result,
a Wii Balance Board connected through the DolphinBar was always
assigned to a Wii Remote slot (Player 1), and games that request a
Balance Board never detected it.
Use Wiimote::IsBalanceBoard() to route balance boards into the
balance_boards results, matching the Linux and Windows scanner
backends. Tested on an AYN Thor (Android 13) with a Mayflash
DolphinBar in Mode 4 running Wii Fit Plus: the board is now detected
in the Balance Board slot.
