USB: ftdi_sio: Add USB Product Id for ELV HS485

USB product id registration for the ELV HS485 USB adapter (www.elv.de) to
their home automation bus system. Applies to 2.6.26.

Signed-off-by: Andre Schenk <andre@melior.s.bawue.de>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>